Utilities 9
QR codes, UUIDs, Unix timestamps, dice probability and more
The small conversions that interrupt real work: what time that meeting is for the other office, how many millimetres that measurement is, what identifier to use for a new record.
// Tools in this category
QR Code Generator
Turn text, a URL, Wi-Fi details or contact information into a QR code and download it as PNG or SVG. Generated in your browser, with no tracking redirect.
UUID Generator
Generate version 4 UUIDs in your browser using crypto.randomUUID. Produce one or many at a time and copy them individually or all at once.
Unix Timestamp Converter
Convert a Unix timestamp to a readable date and a date back to a timestamp, in seconds or milliseconds, with the current epoch time always on screen.
Time Zone Converter & World Clock
Convert any date and time across 45 cities, watch a live world clock with daylight saving handled automatically, and plan meetings in your browser.
Number Base Converter
Convert a number between binary, octal, decimal and hexadecimal at once. Handles arbitrarily large values with BigInt and negative numbers too.
Byte Converter
Convert a size between bytes, KB, MB, GB, TB and PB at once. Uses 1024 as the step, the convention operating systems and developers actually use.
Unit Converter
Convert length, weight, temperature, area, volume, speed, time, angle, pressure and energy across 80+ units at once. Runs entirely in your browser.
HTML Table ⇄ CSV
Convert an HTML table into CSV, or turn CSV into a clean HTML table. Includes a rendered preview and a header row toggle. Runs in your browser.
Dice Probability Calculator
Work out the exact probability of rolling a given total with any number of dice, with a full distribution, cumulative odds and a roll simulator.
// Time zones are harder than they look
Adding or subtracting a fixed number of hours works until it does not. Daylight saving transitions move by region and by date, the gap between London and New York is five hours for most of the year and four for a fortnight in spring, and India and parts of Australia sit on half-hour offsets. A converter that applies the actual rules for a given date removes the guesswork, which matters most when you are scheduling something that people will show up to.
// Converting units without rounding surprises
Unit conversion looks trivial and mostly is, but the failure modes are consistent: mixing up US and imperial gallons, assuming a US fluid ounce and a UK fluid ounce are the same, or losing precision by rounding at an intermediate step. Converting in one pass from a canonical base unit avoids the accumulated error, and seeing the full precision lets you decide where to round rather than having it decided for you.
// What to reach for
The Time Zone Converter compares a moment across several cities at once, with daylight saving applied for the date you pick. The Unit Converter handles length, weight, area, volume, temperature, speed, pressure and energy. The Unix Timestamp Converter goes between epoch values and readable dates in both seconds and milliseconds. The Byte Converter steps between bytes and petabytes. The Number Base Converter shows binary, octal, decimal and hex together. There are also a QR code generator, a UUID generator, an HTML table to CSV converter and a dice probability calculator.
// Utilities: frequently asked questions
- Does the time zone converter handle daylight saving?
- Yes. Conversions use the browser Intl time zone database, so the offset applied is the one in force on the date you select rather than a fixed number of hours.
- Can the unit converter convert a clock time between regions?
- No. Its time category converts durations, such as minutes to hours. To move a wall-clock time between regions, use the Time Zone Converter, which applies daylight saving rules.
// Other categories
Looking for something that is not here yet? The Japanese edition of this category lists 10 tools. The tools themselves work the same way regardless of the language of the surrounding page.