Developer tools with built-in AI — private by default

Format, convert and encode, AI-repair broken JSON, turn JSON into code and plain English into cron — all in your browser. Free, private, no sign-up.

JSON Formatter & Validator

Format, validate & minify JSON — right in your browser.

Base64 Encode / Decode

Encode text to Base64 and decode it back — URL-safe option, UTF-8 ready.

Unix Timestamp Converter

Convert Unix timestamps to human dates and back — seconds, milliseconds, UTC & local.

UUID Generator

Generate random UUID v4 and time-ordered v7 — in bulk, instantly.

Diff Checker

Compare two texts line by line and see exactly what was added, removed or kept.

JSON to CSV Converter

Convert a JSON array into clean CSV — open it in Excel, Sheets or Numbers.

URL Encode / Decode

Percent-encode text for URLs and decode it back — component or full-URL mode.

JWT Decoder

Decode a JSON Web Token to read its header, payload and signature — 100% in your browser.

Hash Generator

Generate MD5, SHA-1, SHA-256 and SHA-512 hashes from any text — instantly and locally.

Cron Expression Parser

Parse a cron expression, see each field explained, and preview the next 5 run times.

YAML ↔ Properties Converter

Convert YAML to Properties and back — Spring Boot friendly, loss-aware, 100% client-side.

Why ToolPie

Private by default

Everything runs locally in your browser. Your data is never uploaded.

Instant & lightweight

Static, CDN-served pages that load fast and work on any device.

AI-powered, where it counts

AI repairs broken JSON, generates typed code from JSON, and builds cron expressions from plain English — with the deterministic parser always there to verify.