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ToolWren › Data & Developer Tools

Data & Developer Tools

A toolkit for working with data: format JSON and SQL, convert YAML, CSV and cURL commands, generate hashes and UUIDs, explain cron, and convert Unix timestamps.

13 tools · 100% client-side · nothing is uploaded

⏱️Timestamp

Convert Unix epoch timestamps to human-readable dates and dates back to epoch. Auto-detects seconds vs milliseconds. Runs in your browser.

{ }JSON

Beautify, validate and minify JSON in your browser. Pretty-print with indentation or compress to one line. Private, no upload.

🗂️CSV ⇄ JSON

Convert a CSV table to a JSON array of objects, or JSON back to CSV. Handles quoted fields. Runs entirely in your browser.

🧾YAML ⇄ JSON

Convert YAML to JSON or JSON to YAML in your browser. Supports maps, lists and scalars. Private, no upload.

🌀cURL Converter

Convert a cURL command into ready-to-run Python (requests), JavaScript (fetch) or Node.js code. Runs in your browser.

#️⃣Hash

Generate MD5, SHA-1, SHA-256 and SHA-512 hashes of any text instantly in your browser. Private, no upload.

🆔UUID

Generate random UUID v4 and ULID identifiers in bulk with one-click copy. Cryptographically random, runs in your browser.

⏲️Cron

Translate a cron expression into plain English and preview the next scheduled run times. Free, runs in your browser.

🗄️SQL Formatter

Beautify and indent SQL queries with keywords on new lines for readability. Runs entirely in your browser.

📰Markdown

Convert Markdown to HTML — headings, bold, italic, links, lists and code. Free online Markdown converter.

🧼Strip HTML

Remove all HTML tags from text, leaving just the readable content. Free online HTML stripper.

💳Luhn Check

Check whether a number passes the Luhn checksum used by credit cards and IMEIs. Free online Luhn validator.

🧰JSON ⇄ TOML

Convert JSON to TOML or TOML to JSON in your browser. Handles nested tables and arrays of tables — ideal for Shopify app config, Cargo and pyproject.toml. Private, no upload.

Other categories

Privacy: every tool in this category runs entirely in your browser. Your input is never sent to, received by, or stored on any server — no uploads, no tracking.