What's New

A big round of upgrades. Many branches that used to just point you to a tool now <strong>compute the answer in place</strong> — Black-Scholes options, Reynolds number, beam deflection, safety stock &amp; reorder point, price elasticity, Bloom-filter false-positive rate, cyclomatic complexity, the secretary problem, leap year, quantization SNR, thread pitch, IoU, tf-idf, softmax, CAGR, Wilson score, EAN/UPC check digits, and more. The master map grew to <strong>362 branches</strong> and now marks each one <strong>⚡ Compute</strong> (it calculates for you) or <strong>→ Route</strong> (it sends you to the right tool), so you can tell at a glance what gives you a number. Plus a word-wrap fix for huge results and a 73-case bug sweep.

Added a sixth simulation: a <strong>simple pendulum</strong> you can drag aside and release to swing, with a fading bob trail. Adjust length, gravity, and damping and watch the motion change; the readout shows the small-angle period T=2π√(L/g) alongside the larger-amplitude period (with the amplitude correction) so you can see where the textbook approximation starts to drift. Joins Projectile, Orbit, Collisions, Spring, and Waves.

An interactive physics sandbox with a live visualizer — five real simulations on one canvas. <strong>Projectile</strong>: drag to aim like a slingshot, launch, toggle air drag, and read range/apex/flight-time/impact speed (with the ideal no-air arc drawn for comparison). <strong>Orbit</strong>: fling bodies around a central mass for circular, elliptical, or escape paths (optional mutual gravity + trails). <strong>Collisions</strong>: throw balls and watch momentum stay conserved and kinetic energy hold (elastic) or drop (inelastic) via a restitution slider. <strong>Spring</strong>: a damped harmonic oscillator with a live position-vs-time graph and the natural period T=2π√(m/k). <strong>Waves</strong>: drag two sources to see an interference pattern ripple. Real equations integrated every frame, 100% in your browser. Joins the Double Pendulum in the Science &amp; Engineering instruments.

A detailed street &amp; satellite map you can measure on, down to the foot. Type an address and the map flies right to the spot, then click to trace a property line, fence run, driveway or lot — and read the length in feet/yards/miles or the area in square feet and acres, with a live perimeter and per-segment breakdown. Every point is draggable so you can line it up exactly on the imagery, distances are geodesic and areas use a spherical-earth polygon formula (the same approach mapping apps use), and units flip to metric in one click. Points you draw and all measurements are computed in your browser; only the map tiles and your typed address come from external services (OpenStreetMap / Esri / Nominatim).

File Inspector, but for math. Paste any equation, formula, dataset, unit expression or word problem and Math Inspector identifies what kind of math it is, computes or sanity-checks it, flags bad math, and links you to the right Utilities Bunker tool. Every input is classified against a <strong>350-branch master map of mathematics</strong>, with a working detector for <strong>every one of its 350 branches</strong> &mdash; all 100% client-side. See the changelog for the full feature list.

An interactive, animated chaos playground in one tool: the logistic map with a live cobweb plot, the period-doubling bifurcation diagram, the rotating 3-D Lorenz attractor, a gallery of strange attractors (Rössler, Aizawa, Halvorsen, Thomas, Hénon, Clifford, De Jong), the butterfly effect (two near-identical starts diverging, with the Lyapunov exponent), and the Mandelbrot &amp; Julia sets — click any point of the Mandelbrot to spin off its Julia. Verified maths: logistic Lyapunov = ln 2 at r=4, correct period detection through the route to chaos, bounded attractors. Renders entirely in your browser. For deep fractal zooming see the Fractal Explorer.

Supercharged with five more algorithms: Bellman–Ford (shortest paths with negative weights + negative-cycle detection), Floyd–Warshall (all-pairs shortest paths, shown as a distance matrix), maximum bipartite matching (auto-checks the graph is bipartite, then pairs jobs↔workers etc.), a travelling-salesman approximation (nearest-neighbour + 2-opt for a short tour visiting every node), and a dependency resolver that groups tasks into parallel stages and flags circular blockers. Joins the existing Dijkstra, A*, MST, max-flow, topological sort, cycle detection, components/SCC, coloring and adjacency matrix — all on the same live force-directed graph. Great for wiring, routing, link structure, project planning and dependency trees.

Rebuilt with a clear result hero (both cities side by side with day-of-week, a UTC offset for each, and a “next day / prev day” badge when the date rolls over) and — the big one — a 24-hour meeting-planner strip: two aligned rows where green is working hours and dark is night, so you can spot an overlap at a glance and click any hour to jump to it. Also fixed a bug where the displayed UTC offsets had their sign inverted (it now correctly shows New York as UTC−04:00, not +04:00). Still 53 cities + UTC, DST-aware, two-way live editing and shareable ?from=&amp;to= links.

Now two timers in one. A real Timer mode counts down a duration you set (presets for 1–60 min) with Start / Pause / Resume / Reset / +1 min, a progress ring, and an alarm — a beep loop, a screen flash and an optional desktop notification — when it hits zero. The original Count-down-to-a-date mode keeps its live days / hours / minutes / seconds display. Plus a fullscreen view for classrooms and workouts, and the time remaining in the browser tab title. Fully client-side.

Rebuilt with a prominent result and the features people need: a Points mode (enter earned/possible, not just a percentage), a contribution bar for each category, weight-sum validation, letter grade with +/−, and a target-grade field that tells you what you still need on the remaining weight.

A teacher's grading scale: enter the number of questions and instantly see the percentage and letter grade for every number wrong, colour-coded A→F, with a quick wrong-answers lookup. The fast way to grade a stack of papers.

Paste a set of test scores and apply a curve — add points, set the top to 100, scale, square-root, or shift to a target average — and see the curved scores, new letter grades and the A–F distribution before and after.

Find the GPA you need next term to reach a goal cumulative GPA, from your current GPA, credits and the credits you'll take — with a feasibility check and best/worst-case outcomes (and how many 4.0 credits it would actually take).

Rebuilt with a prominent result and the features people actually need: weighted GPA (Honors +0.5 / AP-IB +1.0 per course), cumulative GPA from your prior GPA + credits, academic standing (Dean's List etc.), Pass/Withdraw/Incomplete grades excluded from the GPA, an optional A+ = 4.3 scale, percentage equivalent, and step-by-step working.

Upgraded from BigInt integers to a full exact-rational engine, so it now does huge DECIMALS too — 0.1 + 0.2 is exactly 0.3 (no float error), 10/4 is the exact fraction 5/2, and 1/3, √2, π, e and exp() are shown to any number of decimal places (set the precision, up to 20,000). All the integer power is unchanged: 1000!, 2^4096, modpow, gcd, isprime, fib remain exact.

Type a logic expression and get everything: truth table, exact minimal simplification via Quine–McCluskey (SOP &amp; POS), Karnaugh map (1–4 vars), a logic-gate diagram, NAND-only / NOR-only conversions, and an interactive binary evaluator. Supports AND/OR/NOT/XOR/NAND/NOR/XNOR as words or symbols (&amp; | ! ^ + apostrophe, implicit AND). A·(B + C′) → AB + AC′. Fully client-side.

2D computational geometry with a live canvas: polygon area & centroid (shoelace), point-in-polygon (ray casting), convex hull (monotone chain), line & circle intersection, bounding box, a Bézier curve inspector (point/tangent/length/split), SVG path math (length & bbox), and Douglas–Peucker polyline simplification. For graphics, CAD, GIS and game dev. Fully client-side.

Real engineering/fabrication 3D math: vector calculator (dot/cross/angle/projection), 3D distance (point–point/line/plane), plane equation from 3 points, line-plane intersection, surface normals, rotation matrices (axis-angle & Euler), a full quaternion calculator (multiply/conjugate/axis-angle/matrix/rotate/slerp), Cartesian↔spherical↔cylindrical transforms and 2D/3D point rotation — with an isometric 3D view. For CAD, game dev, robotics and graphics. Fully client-side.

Paste data points and find the best-fit model automatically: linear, polynomial (quadratic/cubic), exponential, logarithmic and power regression, ranked by R² and adjusted R² (so it won't overfit a polynomial to a straight line). Includes a scatter + fit-curve chart, residual chart, a model-comparison table and a prediction table. For science, tuning, testing and business. Fully client-side.

Advanced statistics in one tool: normal/binomial/Poisson distributions, descriptive stats, outlier detection, linear regression, Pearson correlation matrix, confidence intervals, one/two-sample t-tests, z-test, chi-square (goodness-of-fit & independence), one-way ANOVA, and Monte-Carlo simulation. Paste CSV data; exact p-values from the real distribution functions (erf, incomplete gamma/beta). Charts included. Fully client-side.

Build signals from sine waves (or square/saw/triangle presets), run the FFT, and see the waveform and frequency spectrum live: peak/harmonic analysis with THD, aliasing detection vs the Nyquist limit, an ideal low/high/band/notch filter preview (original vs filtered), and a sampling-rate / Nyquist calculator with note↔frequency, period and wavelength math. For audio, electronics and data. Fully client-side.

Real graph & network algorithms with a force-directed visualizer: shortest path (Dijkstra), A* pathfinding, minimum spanning tree (Kruskal), max-flow (Edmonds–Karp), cycle detection, connected components / SCC (Tarjan), adjacency matrix, greedy graph coloring and topological sort (Kahn). Type an edge list, pick an algorithm, see the result highlighted. For routing, dependency trees, wiring and scheduling. Fully client-side.

Find best values: linear programming with a feasible-region graph (maximize 40x+30y subject to 2x+y≤100, x+y≤80 → x=20, y=60, profit=2600), the simplex method for 3+ variables, and gradient-descent nonlinear optimization with a contour heat-map visualizer. Detects unbounded and infeasible problems. Built for cost/profit and engineering design. Fully client-side.

Root finding (Newton–Raphson with exact symbolic derivative, bisection, secant), ODE solvers (Euler, Runge–Kutta RK4), and numerical integration (trapezoid/midpoint/Simpson) & differentiation (forward/backward/central) — each with a full step-by-step iteration table and error estimates. Find the root of x³ − x − 2 → x ≈ 1.52138. Fully client-side.

Matrices, vectors, systems and transformations in one exact tool: add/subtract/multiply, scalar & powers, determinant, inverse, row-reduction (RREF), rank, null space, column space, eigenvalues & eigenvectors, dot/cross product, vector projection, and solving linear systems (2x + y = 5; x − y = 1 → x = 2, y = 1). Exact rational (fraction) arithmetic; eigenvalues exact for rational/surd cases, numeric otherwise. Fully client-side.

Solve ODEs step by step: first-order (direct integration, separable, linear via integrating factor, homogeneous), second-order linear constant-coefficient (characteristic equation + undetermined coefficients), and initial-value problems — plus a numerical RK4 solver, slope fields and phase plots. Every symbolic solution is checked by substituting it back into the equation; if it fails, the tool falls back to a numeric answer instead of showing something wrong. Fully client-side.

A full calculus tool in one page: symbolic derivatives (any order), integrals (table + linear substitution + integration by parts), limits (one/two-sided and at ±∞), Taylor/Maclaurin series, critical & inflection points with the second-derivative test, area under a curve, arc length, related rates, and closed-interval optimization — with a live graph and step-by-step output. Fully client-side.

A browser-based computer-algebra system that manipulates expressions, not just numbers: expand, factor, simplify, solve linear/quadratic equations (exact — including surds and complex roots), rearrange formulas (solve V=I·R for R), partial-fraction decomposition, and an expression-tree viewer. Exact rational arithmetic, fully client-side.

Now exact for integers of any length (BigInt instead of floating point). Adds a hero GCF/LCM result, a prime-factorization breakdown showing min/max exponents, Bézout coefficients (ax+by=gcd), coprime detection, copy buttons, examples, and a clearer step-by-step Euclidean Show Work.

Replaced the two-field A/B layout with a full arbitrary-precision expression evaluator (BigInt, no eval): type 2^4096, 100!, modpow(7,10^18,1000000007), gcd, isqrt, root(k,n), fib, isprime, nextprime and more. Adds operators ^ ! % with implicit multiply, hex/scientific literals, rich readouts (digits, scientific approx, bit length, hex, parity, primality), copy, and clickable history.

Rebuilt with a proper expression parser (no eval), a full scientific keypad with a 2nd-function key, Rad/Deg/Grad modes, memory (MC/MR/M+/M−) and Ans, and clickable history. Adds hyperbolics, nCr/nPr, gamma, log(b,x), root(n,x), implicit multiplication and more.

Convert numbers to and from dozenal (base 12), the system many argue is better than decimal — with X/E (or A/B) for ten and eleven and the conversion working shown.

Convert decimal to and from base-60, the ancient Babylonian system still behind our minutes, seconds and degrees — shown in comma notation and as cuneiform 𒁹/𒌋 numerals.

Convert decimal to and from Maya vigesimal (base 20), drawn in the dot-and-bar numerals (a bar = 5, a dot = 1, a shell = 0).

Convert numbers to and from the factorial number system (factoradic), where each place weight is a factorial — and see the permutation it indexes (its Lehmer code).

Write any number as a sum of non-consecutive Fibonacci numbers (its unique Zeckendorf representation) and its Fibonacci code — e.g. 100 = 89 + 8 + 3.

Express any fraction as a sum of distinct unit fractions (1/n) using the greedy algorithm — e.g. 2/3 = 1/2 + 1/6 — with the steps and an exact sum check.

Convert a number to and from unary (n marks) and grouped tally marks (fives) — base 1, the simplest number system there is.

See how a number is stored as a posit (the modern floating-point alternative) with configurable nbits/es — sign, the variable-length regime, exponent and fraction fields, hex and value. Presets for Posit(8,0), (16,1), (32,2).

Find any fraction's place in the Stern-Brocot tree — its left/right path from 1/1, the mediant fractions visited (the best rational approximations), and the link to its continued fraction.

Break a number into a mixed-radix system where each place has its own base — days:hours:minutes:seconds, degrees:arcmin:arcsec, miles:yards:feet:inches, or a custom radix vector.

Turn a number or fraction into its continued fraction [a0; a1, a2, …] and list the convergents — the successive best rational approximations (e.g. π → 22/7, 333/106, 355/113) with their error.

Reveal the exact rational an IEEE-754 double actually stores (0.1 is really 3602879701896397/36028797018963968, not 1/10), its full exact decimal, and the simplest fraction that still rounds to the same float.

Define your own floating-point format (any exponent/mantissa bits) and see the bit fields, hex, value stored and rounding error — with presets for the FP8 ML formats (E4M3, E5M2), FP16, bfloat16, FP32 and FP64.

See the floating-point spacing at any value: the ULP (unit in the last place), the next representable float up and down, and how many floats lie between two numbers — single or double precision.

Compute the simple integrity checks over a sequence of bytes — even/odd parity, XOR checksum, modular sum, two's-complement checksum, the Internet (RFC 1071) checksum and LRC — side by side.

Convert a number between plain decimal, scientific notation, engineering notation (exponent a multiple of 3) and SI-prefix form (1.5k, 4.7µ, 2.2M) — type any of them in.

Convert decimal to and from balanced ternary (base 3 with digits −1, 0, +1, written T 0 1) — which needs no sign for negatives — with the conversion steps shown.

Convert decimal to and from negabinary (base −2), which represents both positive and negative integers using only 0s and 1s with no sign bit, with the positional working shown.

Convert spreadsheet column letters to and from their number (A=1, Z=26, AA=27 … XFD=16384) — the bijective base-26 system Excel and Google Sheets use — with the place-value working shown.

Encode and decode big numbers in Base36, Base58 (the Bitcoin/IPFS alphabet) and Base62 (short URLs / IDs), shown side by side. Exact at any size via BigInt.

Convert a whole number between any two bases from 2 to 64, with an optional custom digit alphabet and the positional-expansion / division working — for the radices the named converters don't cover.

Convert real numbers to and from fixed-point Qm.n (the format used in DSP/embedded code with no FPU): raw stored integer, binary/hex, value represented, quantization error, resolution and range.

Convert decimal to/from Binary-Coded Decimal — 8421 nibbles, packed hex and Excess-3 — with a per-digit code table and invalid-nibble detection when decoding.

See a signed integer in sign-magnitude, one's complement and two's complement side by side at 8/16/32/64-bit, with the two-zeros and asymmetric-range differences explained.

Lay out named bit-fields in a register word, pack them into the hex/binary value (with a coloured bit-map and overlap/overflow checks), or decode a word back into its fields.

Flip a hex value between big-endian and little-endian at 16/32/64-bit, with the byte layout shown and the unsigned value of each interpretation. Handy for networking, file formats and embedded work.

Convert decimal fractions to and from binary (0.625 ↔ 0.101) with the repeated-multiply-by-2 working shown, and a clear “repeating / truncated” label for fractions like 0.1 that have no exact binary form.

See how a number is stored as 16-bit half precision (FP16) and bfloat16 — the formats used in machine learning — with sign/exponent/mantissa bits, hex, the value stored and the rounding error. Companion to the IEEE 754 tool.

Set, clear, toggle or test a bit; population count; leading/trailing-zero count; rotate left/right; reverse bits — at 8/16/32/64-bit, with a clickable bit display.

See how a decimal number is stored as a 32-bit or 64-bit IEEE 754 float — sign, exponent and mantissa bits broken out, the hex pattern, the exact value stored and the rounding error, plus subnormal/Infinity/NaN handling.

Show a signed integer in 8/16/32/64-bit two's complement — binary and hex, signed vs unsigned readings, the invert-and-add-one steps, and overflow warnings.

AND, OR, XOR, NOT, NAND/NOR/XNOR and shifts on two numbers (decimal, hex or binary), with the operands and result lined up bit-by-bit in binary, decimal and hex.

Add, subtract and multiply two numbers directly in binary, octal or hex — with the carries and borrows shown column by column and a decimal cross-check.

The 42 separate binary/decimal/octal/hex/Roman/words/scientific converters are now a single page: type a number in any format and see every representation at once, copy any of them, and open the step-by-step working. All the old links redirect here.

Instead of a single “standard drinks” number, build your actual drinks: pick from 13 types (light/regular/craft beer, 24oz malt liquor like Steel Reserve, hard seltzer, wine, fortified wine, shots, cocktails…) with editable size and ABV, add as many as you like, and it sums the real ethanol for a closer estimate. (Still an estimate — see the on-page disclaimer.)

Added a Practice button: the tool plays a random character in Morse and you type what you hear, with instant right/wrong feedback (answer shown in dots and dashes), a running score and percentage, your current streak and a saved best streak. Choose letters, numbers, punctuation or everything, and Replay / Reveal / Skip as you go.

Expanded to 9 locales (US, Canada, UK, Australia, Germany, France, Spain, Italy, Netherlands) and a fuller record — now also username, test password, company, job title, website, country and a documentation-range IP. Click any field to copy it, or download the whole batch as JSON or CSV.

Every problem-solving calculator and converter now shows its work — step-by-step with your actual numbers substituted in. Added to ~39 more tools across Numbers &amp; Math (geometry, arithmetic, statistics, converters), Automotive, plus age, coordinate, pressure, altitude, currency, GPA and timezone tools. Also fixed a long-standing crash in the general base converter.

All 42 number-system converters (binary, decimal, hex, octal, Roman, scientific, English words) now have a “Show work” panel that explains the conversion step by step — positional expansion, repeated-division remainders, Roman subtraction and more — not just the answer.

Paste garbled text like “café”, “’” or ““Hello— and get the correct original back — café, ’, “Hello”. Repairs UTF-8 decoded as Windows-1252/Latin-1 (including double-encoded text), explains what went wrong, shows the damage character by character, and lets you copy the fix. Runs locally.

Search any character, symbol or emoji by name, keyword or code point (U+2014, 0x2014, 8212) and copy it in any language — HTML, JavaScript, CSS, JSON, PHP, Python or SQL. Plus an Inspect mode that reveals invisible/zero-width characters, bidi marks, lookalikes, mixed-script spoofing and mojibake, with a one-click cleaner. Runs locally.

A browsable reference of common developer errors — browser, HTTP, JavaScript, SQL, PHP, Linux/server and SSL/DNS — each with a plain-English meaning, common causes and fixes. Search by code (404, 1045) or keyword. Powers the Explain This Error tool too.

Paste any error message — browser, HTTP, JavaScript, SQL, PHP, Linux/server or SSL/DNS — and get a plain-English explanation plus the likely fixes. Runs locally; nothing is uploaded.

See the hidden metadata in your files — author, GPS location, software, timestamps, "last modified by" — and scrub it out. Photos, PDFs, Word/Excel/PowerPoint and audio. Nothing uploaded.

Drop a broken file and fix it in your browser: correct a wrong extension, trim junk bytes, rebuild a damaged ZIP/Office archive or PDF, or remux a media file that won't play. Nothing uploaded.

Convert video between MP4, WebM, MOV, MKV and animated GIF — resize, trim, change frame rate or mute — entirely in your browser with a real ffmpeg engine. Nothing uploaded.

Extract the audio from a video you own (MP4, MOV, M4V, WebM, Ogg) and save it as MP3 or WAV — instantly in your browser, nothing uploaded.

Convert almost any audio in your browser: WAV/MP3 instantly, plus FLAC, ALAC, AIFF, AAC/M4A, OGG, AC-3 and WMA via an on-demand engine. Trim, normalize, set bitrate/rate/channels. Nothing uploaded.

Identify a bulb by base & shape, convert old watts to lumens and the right LED (with yearly cost), visualize color temperature, and look up car bulb numbers.

Tune any car/home/headphone system: play pink noise, measure with your mic, and get plain cut/boost guidance mapped to your own named controls.

Draw any shape and watch a chain of rotating circles retrace it via the Fourier transform.

Zoom into the infinite detail of the Mandelbrot and Julia sets with smooth coloring; save a PNG.

Generate pure tones, tune an instrument with your mic, and test your hearing range.

A real-physics double-pendulum simulator with glowing trails and ghost pendulums to show chaos.

Search now ranks the best matches first, handles multi-word queries in any order, shows a See-all link and result types, suggests popular/recent tools, and supports the Cmd/Ctrl+K shortcut.

Now move & resize shapes on the canvas, name each area, set per-material prices, and save/load your designs.

Site-wide mobile pass: larger tap targets, properly labelled inputs, and no more horizontal overflow on phones.

The Before/After compare boxes are now full-width and much taller, so long text is far easier to compare.

Solve dy/dx=f(x,y) by Euler vs Heun vs RK4 with a step table and graph, plus an Euler's-formula unit circle and an e explorer.

Draw your project to scale — squares, circles, curves — and get cubic yards, bags, and tons per material.

Hot-mix asphalt tonnage for driveways and lots from area and compacted thickness.

Block count and mortar for a wall, with door/window openings deducted.

Stud count and plate lumber for a framed wall at 12/16/24" on-center.

Cut volume in cubic yards, soil swell, and truckloads for digging and grading.

Project tax-free Roth IRA growth from contributions, return, and years to retirement.

Compare the true net cost of buying vs renting over the years you plan to stay.

Monthly payment, total interest, payoff time, and the savings from extra payments.

Rough monthly benefit estimate by claiming age using the PIA bend-point formula.

See the federal marriage penalty or bonus from filing jointly vs as two singles.

Annual and monthly pension, replacement ratio, and a lump-sum equivalent.

Down payment, loan amount, monthly payment, and whether PMI applies under 20%.

Projected future college cost with education inflation, and the monthly savings needed.

Monthly lease payment from cap cost, residual, money factor, and tax — with equivalent APR.

Compare your current debts against a consolidation loan to see the interest saved.

Payment, total interest, and net cash after origination fees.

Monthly payment and total interest for a boat loan, with sales tax financed in.

What you walk away with after commission, payoff, closing costs, and concessions.

Body fat % by the AR 600-9 tape (circumference) method.

Daily carb grams from your calories and target percentage, plus a fiber goal.

Daily fat grams and a saturated-fat limit from your calories and target percentage.

How far along you are in weeks, your trimester, and the estimated due date from your LMP.

Estimated conception date and fertile window from your last period or due date.

Now local-first: conversion runs offline from an editable rate, with live rates as an opt-in one-tap fetch.

Added a door/window openings deduction so estimates aren't inflated by area you won't brick.

Fixed long filenames overflowing and breaking the layout.

Calculator results now show as a prominent hero card plus supporting cards on ~280 tools.

Every construction calculator gained how-to steps, FAQs, use cases, and related links; duplicate listings removed.

All finance calculators gained how-to, FAQs, and examples; duplicate listings cleaned up.

Every health calculator gained guides, FAQs, and use cases; duplicate listings removed.

Massively upgraded into a full forensics & reverse-engineering suite: reads ~640 file formats (584 parsers), with PE/ELF/Mach-O analysis, an x86 disassembler + decompiler + CPU-emulator sandbox, crypto & code-signing detection, packer/obfuscator ID, and IOC/network intel — all in your browser.

Plot one or more functions on an interactive, zoomable graph.

Watch bubble, quick, merge, heap and more sorts animate step by step.

Design CSS easing curves with a draggable handle and a live motion preview.

Turn a regular expression into a readable railroad diagram.

Generate SEO, Open Graph and Twitter meta tags with live search & social previews.

Build JSON-LD structured data (Organization, Article, Product, FAQ and more).

Assemble a robots.txt from templates, with AI-bot blocking and a sitemap line.

Convert JSON to CSV and back, flattening nested keys.

Infer clean TypeScript interfaces from any JSON.

Build a .gitignore from curated language and tool templates.

A visual Flexbox playground that copies the CSS for you.

Build a CSS grid visually and copy the layout code.

Fluid-type CSS clamp() with the math worked out and a live scaling preview.

Turn text (with accents) into clean URL slugs, in batches.

Encode an image to a base64 data-URI with ready CSS/HTML snippets — fully local.

Assemble common Apache .htaccess rules from checkboxes and download the file.

Reduce ratios and solve a missing width or height.

Audit a page's HTML for SEO, accessibility, best practices and performance with Lighthouse-style scores — all in your browser.

Pick colors and convert between HEX, RGB and HSL.

Check text/background contrast against WCAG AA and AAA.

Extract a color palette from any image you drop in.

Preview how an image looks under different types of color blindness.

Grab any pixel's color from your screen or an image.

Design CSS box-shadows with a live preview and copy the code.

A spin-the-wheel random picker for names, choices or prizes.

Flip a virtual coin once or many times and see the tally.

Generate the full truth table for any boolean/logic expression.

Reference charts for common power, USB, video and audio connectors.

Look up NEMA plug and receptacle configurations by amperage and voltage.

Exact age in years, months and days, plus totals and your next birthday.

A focus timer with a dial, chimes and a session counter.

A precise stopwatch with laps and keyboard shortcuts.

Real-time spectrum analyzer and spectrogram from your mic or an audio file.

Read text aloud with your device voices, with adjustable rate, pitch and volume.

Turn images or text into ASCII art.

Combine multiple PDFs into one, entirely in your browser.

Split a PDF or pull out just the pages you need.

Rotate PDF pages and save the result.

Convert PDF pages to JPG or PNG images.