Tukuk-OS🧰 Everyday Tools
Converters · calculators · checkers · generators — all computed on your device
The honest kind of useful. Twenty-six small tools that people actually search for — and that do their whole job inside your browser. Your text, your files, your dates, your passwords and your colours are processed on your own machine and never sent to us; there is no API to be down, no account, no download, and no tracking. The page works even after it has loaded on a plane.
In the toolbox
📐 Unit converter — eight categories with exact, definition-based factors (1 inch really is 2.54 cm); every unit in the category updates at once.
📅 Date & age calculator — counting days between deadlines, ages to the day, working days between dates, and the reliable days-until-birthday.
🎨 Colour & contrast checker — the official WCAG maths with pass/fail badges, and it suggests the nearest colour that does pass.
🔐 Password generator — uniform random picks from your browser’s cryptographic generator with real entropy numbers, not a smiley face.
✂️ Text toolkit — word & reading time counts, six case styles, URL and Base64 encode/decode, and SHA-256 hashes for file or text integrity.
❤️ BMI & calorie calculator — the health numbers that come from arithmetic: BMI bands, healthy weight range, and calorie needs from the published Mifflin-St Jeor equation.
🖼️ Image compressor — shrink photos and screenshots with quality and resize controls; your file is re-encoded on your own device and never uploaded.
📖 Dictionary & translator — word meanings and translation across dozens of human languages, plus ancient scripts and playful animal/alien/sound codes, all with spoken pronunciation.
🧮 Percentage calculator — the four questions people actually type: what is X% of Y, X is what percent of Y, percent change, and adding or subtracting a percentage — with the arithmetic shown.
🏦 Loan & compound interest calculator — monthly payment, total interest, the real savings from overpaying, and what regular saving grows into after compounding.
🔳 QR code generator — links, text and Wi-Fi credentials into a scannable code with L/M/Q/H error correction, drawn on a canvas and downloaded as a print-ready PNG.
📍 What is my IP? — your public address, the ISP and inferred city from a keyless database, and the browser fields any site can read, all explained instead of hidden.
⏱ Unix timestamp converter — epoch to date and back, seconds-versus-milliseconds auto-detection, ISO 8601, time zones and a live clock.
🎲 Random numbers & dice — unbiased integer ranges, d4–d100 rolls and a raffle-style list picker from the operating system’s cryptographic generator.
📄 PDF tools — merge, extract, delete, rotate and split pages; the file is opened and re-saved by your browser, so the document never reaches a server.
🧩 JSON formatter — format, minify and validate with the exact line and column of an error, keeping large numbers and key order intact.
🔑 Checksum & hash — MD5 through SHA-512 for text or a whole file, so a download can be checked against its published value without handing the file to anyone.
🔁 Base64 encoder — correct UTF-8 both ways, URL-safe output and a file turned into a data: URL, with the caveat that encoding is not encryption.
🌍 Time zone meeting planner — up to eight cities, every hour of the chosen day, with true UTC offsets and the best overlap named for you instead of counted by hand.
🆔 UUID generator — random v4 and time-ordered v7 in bulk, plus a decoder that reports the version, variant and any timestamp hiding inside an identifier.
⏰ Cron expression explainer — a schedule in plain English with its next ten runs on your clock, every field range-checked, and the day-of-month/day-of-week OR trap spelled out.
🔍 Regex tester — write a pattern, see live match highlighting with groups; a common-pattern library gets you started on email, URL and IPv4.
📊 CSV viewer & converter — paste delimited text, get a formatted table and clean JSON, with RFC 4180 quoting handled correctly.
🔀 Text diff — compare two blocks of text line-by-line or word-by-word; see additions and deletions highlighted instantly.
🔗 URL parser & encoder — break a URL into every component, or encode/decode query values side-by-side to catch the classic percent-encoding bug.
🔣 Character & Unicode reference — inspect code points, HTML entities, UTF-8 bytes and UTF-16 units for any character; a quick-reference table for typographic symbols.
🧭 Compass & bearing — a live on-screen compass off your phone’s magnetometer, with the great-circle bearing and distance to any world city; a desktop without a sensor falls back to a manual dial.
Why browser-local, and why it matters to you
Most “free tool” sites ship your input to a server, paste eight ads around it and remember nothing about how the maths works. Here every answer comes from arithmetic your browser can verify: unit factors from international definitions, date counts from the Gregorian calendar itself, contrast ratios from the published WCAG formula, passwords from the operating system’s random source. That makes them private by construction — a password page that runs locally is not a promise, it is a fact you can check in your network tab.