Utilities

Generators, converters and practical calculators for everyday tasks: QR codes, passwords, UUIDs, hashes, date and tip calculations, unit conversion and an on-screen ruler.

All 10 Utilities

📱

UUID Generator

Generate unique identifiers (UUID/GUID)

🔄

Online Ruler

Measure lengths on screen with a calibrated ruler

🧮

Unit Converter

Convert length, weight, temperature, speed and area

💵

Tip Calculator

Work out the tip and split the bill to the exact cent

📅

Date Calculator

Count days or business days, and add or subtract dates

Generate: QR codes, passwords and UUIDs

These three make something new each time you ask: a code to scan, a secret, an identifier. A UUID identifies something and a password protects something, so do not use one as the other.

Tool	Use it to	Worth knowing
QR Generator	Put a link, text or contact details into a scannable code	The code holds your content directly, with no redirect service, so it does not expire. Print a test copy at final size before committing.
Password Generator	Create a random password with the length and character types you choose	Generated in your browser and not stored by this site. It passes through your clipboard when you copy it.
UUID Generator	Create 1 to 50 random identifiers at a time	Version 4 only. Standard, uppercase, no-dash and braces formats.

Encode and inspect: Base64 and hashes

Both of these work on text you paste in, and they are easy to confuse. A Base64 string can be turned back into the original text by anyone. A hash cannot be turned back.

Values that have to travel inside a URL are a separate job: see URL Encode/Decode in Developer Tools.

Tool	Use it to	Worth knowing
Base64 Encode/Decode	Carry text through JSON, headers or config files, or read a Base64 string that holds text	Text only, using the standard alphabet. It is an encoding, not encryption.
Hash Generator	Get MD5, SHA-1, SHA-256 and SHA-512 digests of a piece of text	Text only, not files. MD5 and SHA-1 are not safe for security, and a plain hash is the wrong way to store passwords.

Calculate: dates, business days, tips and bills

The Date Calculator counts calendar or business days and adds or subtracts dates. The Tip Calculator works with money in whole cents, so a split shares out every cent.

Tool	Use it to	Worth knowing
Date Calculator	Count days or working days between dates, or add and subtract calendar units and business days	Dates are limited to 1900 through 2100. Choose the weekend and add your own holidays; public holidays are not inferred.
Tip Calculator	Work out a tip, see the final bill and split it between 1 to 100 people with no cent lost	Never adds tax or a service charge to your bill. The currency menu changes the symbol only and converts nothing. Equal splits only.

Convert and measure: colors, units and lengths

If you want to start from the colors in a picture, take them out with the Color Palette tool in Image Tools, then paste a HEX value into the Color Converter.

For a specific conversion such as centimeters to inches, kilograms to pounds or Celsius to Fahrenheit, see Unit Converters. Each of those pages opens the same Unit Converter with the conversion already selected.

Tool	Use it to	Worth knowing
Color Converter	Convert a color between HEX, RGB and HSL, with a live swatch and copy-ready CSS	HEX, RGB and HSL only: no alpha channel, CMYK or named colors.
Unit Converter	Convert length, weight, temperature, speed and area between any two units in the category	Uses exact unit definitions and shows up to 12 significant digits. No volume units yet, and temperature is Celsius and Fahrenheit only.
Online Ruler	Measure a length in millimetres, centimetres or inches against your screen	Approximate until you calibrate it, and worth recalibrating after changing zoom or monitor.

Common questions

Is what I enter sent anywhere?

No. All ten utilities run in your browser. The Online Ruler keeps its calibration in your browser's local storage on your own device so it is still there next visit.

Can I use these on files or images?

Base64 Encode/Decode and the Hash Generator only handle text you type or paste, so they cannot encode an image or produce the checksum of a downloaded file.

Does Base64 or hashing keep a secret safe?

No. Base64 is reversible by anyone, and a plain hash of a short or common value can be looked up in precomputed tables. For a strong secret, generate one with the Password Generator and keep it in a password manager.

Unit Converters: Specific conversions such as cm to inches, kg to lbs and Celsius to Fahrenheit, each with its formula and a table of common values.
Developer Tools: Format JSON, beautify code and percent-encode URLs, which pair with Base64 and hashing.
Color Palette: Take colors from an image before converting them.