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Tool reference

JSON Validator: instructions, examples and limits

Uses the browser’s strict JSON parser.

Open JSON Validator
Processing location: your browser

This tool is registered for local processing. Its tool input is handled in the current page; LittleKit’s product analytics do not include the input value.

What it does

Uses the browser’s strict JSON parser. Comments, trailing commas and single-quoted keys are rejected.

Worked example

{"ready":true} is valid; {ready:true} is invalid.

The example demonstrates the operation. For file-based tools, results depend on the selected file and options.

How the result is produced

Uses the browser’s strict JSON parser. Comments, trailing commas and single-quoted keys are rejected.

Important limits

Input stays in this tab and is never sent to analytics. Limit 100,000 characters. No input is executed.

Choosing the next step

Treat these tools as a local scratchpad. Validate the format before transforming it, keep secrets out of shared screenshots and remember that a decoded token is not an authenticated token. Use the smallest input that reproduces the problem.

JSON FormatterParses strict JSON and serializes with two-space indentation.Base64 DecodeDecodes standard Base64 bytes as strict UTF-8 text.Unix Timestamp ConverterUnix time measures elapsed seconds or milliseconds since 1970-01-01T00:00:00Z.

Related practical guides

See a mismatch between these instructions and the tool? Report a correction with a non-sensitive example.