Free browser-based utilities
Free Online Developer Tools
Browse free browser-based utilities for common development tasks, from formatting JSON and comparing text to inspecting tokens and testing API requests. Choose a tool to get started; no account or installation is required.
Explore 22 developer tools
- JSON FormatterFormat, validate, and minify JSON payloads.
- Markdown PreviewerEdit Markdown and view a safe live preview.
- CSV / JSON ConverterConvert structured tables between CSV and JSON.
- Base64 Encode and DecodeEncode and decode text or data URIs.
- URL Encoder and DecoderEncode URL components or decode percent-encoded text.
- Text Diff CheckerCompare two text inputs and review line changes.
- SQL Formatter & BeautifierFormat SQL with readable clauses and indentation.
- HTML Entity Encoder and DecoderConvert reserved characters to and from HTML entities.
- JavaScript MinifierMinify JavaScript, CSS, or HTML source text.
- Text Case ConverterConvert text into common code naming conventions.
- JSON Schema ValidatorCheck JSON data against common JSON Schema rules.
- Regex TesterTest patterns, flags, and capture groups.
- API TesterSend HTTP requests and inspect API responses.
- JWT DecoderInspect a token's header and claims locally.
- Color Converter & Contrast CheckerConvert CSS colors and test WCAG text contrast.
- Environment File ParserParse .env assignments and flag malformed or duplicate keys.
- OpenAPI ViewerBrowse paths and operations from an OpenAPI JSON document.
- HTTP Status LookupSearch common HTTP response codes and definitions.
- UUID GeneratorGenerate one or more random version 4 UUIDs.
- Hash GeneratorCreate SHA-256, SHA-384, or SHA-512 digests.
- Timestamp ConverterConvert Unix timestamps and date-time values.
- Cron Expression ParserValidate a cron schedule and preview upcoming runs.
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