18 focused tools
Free online developer tools.
Format JSON, and encode or decode Base64 and URLs, with clear error messages.
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3 of 18 tools in Developer
Free online developer tools
Small developer utilities for everyday debugging: pretty-print and validate JSON, convert text to and from Base64, and percent-encode URLs.
What developer tools are available?
A JSON formatter and validator, a Base64 encoder and decoder and a URL encoder and decoder, all with clear error messages.
How do I read the data inside a JWT or Base64 API response?
Copy the part you need (for a JWT, the middle section between the two dots), decode it with the Base64 decoder, which accepts URL-safe Base64, then paste the result into the JSON Formatter.
Is my data sent to a server?
No. Input is processed in your browser and is not sent anywhere by this page, so it is safe for API responses and config files.