Free Online Developer Tools
Simple, fast, browser-based tools for everyday dev tasks. No signup, no tracking.
OpsKit is a collection of free, browser-based utilities built for developers and ops engineers. Convert text lists into Python arrays, JavaScript arrays, or SQL IN clauses. Format and validate JSON. Encode and decode URLs, Base64, and Unicode. Parse Unix timestamps or decode JWT tokens — all instantly in your browser with zero data sent to any server.
List to Array
Convert a list of text into Python list, JS array, JSON array, SQL IN, or CSV.
SQL IN Builder
Paste a column of IDs or values and get a ready-to-use SQL IN (...) clause.
JSON Formatter
Format, minify, and validate JSON. Escape or unescape JSON strings.
URL Encode / Decode
Encode or decode full URLs and individual query parameters, including spaces, Chinese text, and special characters.
JSON String Escape / Unescape
Escape plain text into a JSON string literal, or unescape a JSON string back to readable text with validation.
Base64 Encode / Decode
Encode text to Base64 or decode Base64 back to UTF-8 text, with support for URL-safe tokens.
Unicode Escape / Unescape
Convert text into Unicode escape sequences like \u4f60\u597d, or decode escaped text back to readable characters.
Timestamp Converter
Convert Unix timestamps and date strings. View seconds, milliseconds, ISO 8601, UTC, and local time instantly.
JWT Decoder
Decode JWT header and payload, inspect claims such as exp and iat, and view readable timestamps without sending data anywhere.
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