API Tester & REST HTTP Client Studio
100% Client-Side REST API Client ★ PopularIn-browser REST API request builder and HTTP client. Test GET, POST, PUT, DELETE endpoints, inspect JSON responses, manage headers, query params, auth, environments, collections, and cURL commands 100% client-side.
Initializing sandbox for API Tester & REST HTTP Client Studio...
More in Developer (4)
View all Developer tools →JSON Formatter & Validator
Format, beautify, validate, and minify JSON with interactive collapsible tree explorer, line-number error markers, and JSON5 relaxed syntax support.
YAML Formatter & Validator
Format and validate YAML streams with multi-document support (---), tab indentation warning fixers, block/flow formatting, and YAML to JSON conversion.
XML Formatter & Validator
Format, beautify, and validate XML documents with interactive DOM tree exploration, line-number error reporting, attribute sorting, and XPath copy.
Base64 Encoder & Decoder
Encode and decode UTF-8 Unicode text, files, images, and Data URLs with URL-safe Base64 toggles, line wrapping, and live image preview thumbnails.
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