Developer tools and calculators
Free, fast and private. Every tool runs in your browser, with no sign-up.
Developer
- JSON Formatter
Format, validate and minify JSON with syntax highlighting.
- Regex Tester
Test regular expressions against sample text with live match highlighting.
- Cron Expression Generator
Build cron expressions and read them in plain English.
- Base64 Encoder / Decoder
Encode and decode Base64 with UTF-8 and URL-safe support, or turn a file into a data URL.
- JWT Decoder
Decode JSON Web Token headers and payloads locally.
- UUID Generator
Generate random UUIDs in bulk.
- Hash Generator
Create SHA-1, SHA-256, SHA-384 and SHA-512 hashes of text or files in your browser.
- URL Encoder / Decoder
Percent-encode and decode URLs and query strings.
- Color Converter
Convert colors between HEX, RGB, HSL and more.
- QR Code Generator
Create QR codes for links and text and download them.
- Password Generator
Generate strong random passwords in your browser.
- Lorem Ipsum Generator
Generate placeholder text by words, sentences or paragraphs.
- Diff Checker
Compare two texts line by line with added and removed lines highlighted.
- DNS Lookup
Look up DNS records for a domain over DNS-over-HTTPS.
Calculators
- Percentage Calculator
Work out percentages, changes and percent-of values.
- Standard Calculator
Basic arithmetic with parentheses and keyboard support.
Converters
- Data Converter
Convert between bytes, kilobytes, megabytes and other data units.
- Length Converter
Convert between metric and imperial length units.
- Temperature Converter
Convert between Celsius, Fahrenheit and Kelvin.