Base64 Encoder / Decoder
Encode Unicode text to Base64 or decode it back to text.
Developer toolsJSON Formatter
Format, minify and validate JSON with useful syntax errors.
Processed locally in your browser — your data is not uploaded.Loading your tool…
How to use JSON Formatter
- Paste JSON.
- Choose formatting or minification.
- Process, copy or download the result.
What JSON syntax is accepted?
Standard JSON requires double-quoted keys and strings, with no comments or trailing commas.
No sign-up is required. The calculation or transformation happens in this browser tab and the result is available immediately.
BEFORE YOU RELY ON THE RESULT
Practical guidance
Formatting changes whitespace and indentation after parsing; minifying removes unnecessary whitespace. Both actions first require valid standard JSON.
Validation behavior
The browser JSON parser rejects comments, trailing commas, single-quoted strings, unquoted keys and incomplete values. When possible, Metyris turns the parser position into an approximate line and column and produces no result until the input is valid.
Formatting does not repair malformed data or prove that its fields match an application schema. It confirms syntax and then serializes the parsed value.
Values that need care
JavaScript numbers cannot exactly represent every integer above 9,007,199,254,740,991. Parsing and re-serializing such values can change digits. Duplicate object keys are also unsafe because the parser keeps only the last value.
Key order should not be used as application meaning. Keep an original copy when formatting data you did not create.
Local and practical limits
Input is processed in this tab and is not sent to a Metyris API. The editor accepts up to 2,000,000 characters, but available browser memory and device speed can make a smaller file the practical limit.
Related workflow
- Base64 Encoder / Decoderinspect reversible text encoding
- URL Encoder / Decoderprepare one query or path component
- Hash Generatorcompare content integrity
- Clean and validate data locallyfollow a safer data-checking workflow
A useful next step
Cleaning and validating data locally in your browserSeparate syntax checks, text cleanup, encoding and integrity verification while keeping working data in the browser.Good to know
Why is an error location approximate?+
Browser parsers expose different detail; line and column appear when a character position is available.
Can I download valid JSON?+
Yes. The result can be saved as a .json file.
Is my input uploaded?+
No. This tool runs in your browser and does not send input or results to Metyris or a third-party processor.