Free JSON, CSV, Excel, and Diff Tools
Format JSON, convert Excel or CSV data, and compare text or structured data in your browser.
Developer Tools
Browser-based daily tools for engineers, including JSON, Excel, CSV, arrays, SQL, Markdown, XML, structured diff, time conversion, and code editing.
Excel to Array
Convert Excel or CSV data into Array, JSON, code, table, SQL, YAML, ENV, or XML output.
JSON Parser & Converter
Format, minify, repair, and convert JSON to TypeScript, JavaScript, PHP, Python, Go, YAML, TOML, ENV, CSV, Markdown, XML, and more.
Data Format Converter
Safely detect and convert JSON, YAML, TOML, XML, Excel, CSV, Markdown tables, ENV, query strings, code literals, arrays, and parentheses.
Text Diff Checker
Compare two inputs like git diff and list additions, removals, and changes. Supports text, JSON, Array, Parentheses, HTML Table, JS / TS / PHP / Python / Go data formats, CSV, TSV, YAML, XML, Query String, and ENV.
Time Converter
Convert Unix timestamps and date strings between source and target time zones, view common formats, and adjust days, hours, minutes, or seconds.
Code Editor
A lightweight code editor with syntax highlighting, preview, find and replace, formatting, local tab management, and practical shortcuts.
Everyday Tools
Small browser tools for countdowns, quick todos, raffles, Chinese text conversion, and common text workflows.
Countdown Timer
A task countdown timer with a timer name, notes, todos, local saving, share links, file backup, and operation history.
Quick Todo
Drop a quick note here before it becomes a real task. Title, notes, time, and checklist are all optional, with sharing and Google Calendar when useful.
Raffle Picker
Import entries, set prizes and winner chances, then run a trackable raffle.
Recommended Tools
External tools and software I genuinely find useful enough to recommend to engineer friends.