Developer Tools
Format, validate, encode and decode โ JSON, Base64, URLs, UUIDs, timestamps, regex.
8 tools available
API Tester
Send HTTP requests with headers, auth and a JSON body, and inspect the full response.
Base64 Encoder / Decoder
Encode text to Base64 and decode it back, with full Unicode and URL-safe support.
JSON Formatter
Pretty-print, minify and inspect JSON with precise error positions.
JSON Validator
Check JSON validity and get a structural summary โ depth, key count and type breakdown.
Regex Tester
Test regular expressions live with highlighted matches, capture groups and replace.
Timestamp Converter
Convert Unix timestamps to human dates and back, in local time and UTC.
URL Encoder / Decoder
Percent-encode and decode URLs and query parameters, with a query string breakdown.
UUID Generator
Generate cryptographically random UUIDs in bulk, with formatting options.
About these developer tools
The daily grind of development involves a lot of small transformations โ pretty-printing an API response, decoding a Base64 blob from a log file, checking whether a regular expression really matches what you think it does.
Doing that on a public website means pasting production data into someone else's server. Every developer tool here is client-side JavaScript: the payload you paste stays in the tab, and the page keeps working if you go offline.
The one tool that necessarily uses the network is the API tester, and even there the request goes straight from your browser to the address you type โ never through this site. That is also why it is bound by the browser's CORS rules, which the tool explains rather than papers over.
Other categories
Calculators
Everyday money, health and date maths โ loans, EMI, interest, GST, BMI and more.
10 tools
Text Tools
Count, clean, sort and reshape text โ word counts, case conversion, duplicate removal.
7 tools
Converters
Unit conversion for length, weight, temperature, speed, data, time, area and volume.
8 tools