Fast, privacy-first utilities for JSON, CSV, strings and cryptography.
Everything runs locally in your browser.

JSON Validator

Validate, prettify, and minify JSON data

JSON Key Counter

Count keys and array elements in JSON

JSON → CSV

Convert JSON arrays to CSV format

CSV -> JSON (Drag & Drop)

Convert CSV files to JSON format

String Length Counter

Count characters, bytes, and lines

Base64 Encode/Decode

Convert strings to/from Base64

HMAC Signature Generator

Generate cryptographic signatures