SweetcraftJSON formatter, Base64 & URL codec
Format valid JSON and encode or decode UTF-8 Base64 and URL components in your browser.
About this tool
Three small developer utilities share this page: a JSON formatter that validates and pretty-prints JSON, a Base64 encoder and decoder for UTF-8 text, and a URL component encoder and decoder for query strings and parameter values. They exist for the moments when you are staring at an unreadable API response or a mangled URL parameter and need a quick, predictable answer.
Each tool is deliberately literal. Formatting never repairs invalid JSON — and because it parses with JavaScript, integers beyond its safe precision can change and duplicate keys keep only their last value. Base64 is an encoding, not encryption: anyone can decode it. The URL codec works on a single component, not a whole URL, and a plus sign stays a plus sign.
How to use JSON formatter, Base64 & URL codec
- Choose JSON formatting, Base64 encoding/decoding, or URL component encoding/decoding.
- Paste text or load a UTF-8 text file up to 5 MB.
- Run and review the result before copying or downloading it.
Keep the original files and inspect the exported result before publishing or sharing it.
Frequently asked questions
Does Base64 encrypt my text?
No. Base64 is reversible encoding and offers no secrecy. This tool accepts standard padded Base64, not the URL-safe variant.
Why did URL decoding fail?
Malformed percent sequences or invalid UTF-8 cannot be decoded. This is a URL component codec: it does not parse a complete URL, and a plus sign stays a plus sign.
Does formatting repair JSON?
No. JSON must be valid. Formatting uses JavaScript parsing: integers beyond its safe precision can change, duplicate keys retain only their last value, and original whitespace is replaced.