A collection of online utilities to help you work efficiently.
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How many units do you need to sell before making a profit? The break-even analysis tells you exactly. Learn the formula, understand fixed vs variable costs, and use an online calculator for pricing and sales planning.
JWT is the standard for modern API authentication. Learn the three-part structure of JWTs, how to decode and verify them, common security vulnerabilities, and how to debug JWT tokens online.
Switching between HEX, RGB, and HSL color formats is a daily task for designers and developers. Learn what each format means, when to use which, and convert any color value instantly online.
Every photo contains hidden data — when and where it was taken, your camera model, even GPS coordinates. Learn what EXIF metadata is, the privacy risks it creates, and how to view or strip it online.
Regular expressions are powerful but hard to remember. Get a quick-reference cheat sheet for common regex syntax, ready-to-use patterns for emails, phone numbers, and URLs, and test your regex in real time online.
Net worth is the most honest measure of financial health — not income, not savings rate. Learn how to calculate your net worth, track it over time, and grow it systematically.
How much money do you actually need to retire comfortably? Learn the 4% rule, calculate your retirement savings gap, and see how starting earlier dramatically changes your outcome.
Seen a number like 1700000000 in your logs or API response? That's a Unix timestamp. Learn what it means, the difference between seconds and milliseconds, and convert any timestamp to a readable date instantly.
Most people overestimate their tax burden by confusing marginal and effective tax rates. Learn how progressive tax brackets work, compare income tax systems across countries, and calculate your real tax bill instantly.
Can't open or upload a WEBP file? Learn what WEBP is, why it's everywhere now, and how to convert WEBP to JPG or PNG online — or convert the other way. Free, instant, no software needed.
PNG files taking up too much space? Learn when to convert PNG to JPG, how much file size you'll save, and convert multiple images at once — free, no software, instant download.
Traveling abroad, sending international payments, or doing business across borders? Learn how exchange rates work, understand bid/ask spreads, and convert any currency pair instantly with a live rate tool.
PDF too large to email or upload? Learn how to compress PDFs online in seconds, understand what makes PDFs large, and choose the right compression level for your needs — completely free.
Ever wondered why your loan balance barely moves in the early years? Loan amortization explains how each payment splits between principal and interest — and shows you exactly how much you'd save by paying extra.
UUIDs are used everywhere in software — database primary keys, session IDs, file names. Learn the difference between UUID v1, v4, and v7, understand collision probability, and generate UUIDs instantly online.
Your gross salary isn't what hits your bank account. Learn how income tax, social security, and other deductions are calculated in different countries — and use an online calculator to find your exact take-home pay.
Learn when and why to resize images, recommended dimensions for major platforms, and how to resize any image to exact pixel dimensions for free online — no software needed.
Learn how image compression works, the difference between lossy and lossless, and how to compress images without visible quality loss. Free online tool with batch support.
Staring at a wall of minified JSON? Learn how to format, validate, and debug JSON instantly online — plus a guide to the most common JSON syntax errors and how to fix them.
High credit card interest rates can make debt feel permanent. Learn how minimum payments trap you, compare payoff strategies, and use a calculator to create the fastest debt-free plan.