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Free browser tool

JSON Formatter

Format, validate, minify, sort object keys, sample, inspect depth, top-level keys, path previews, value mix, share risk, review checks, top-level entries, and copy formatted JSON, minified JSON, sorted-key JSON, path reports, structure reports, or parse errors in your browser.

Updated 2026-07-06

Examples

Waiting for JSON input.

Type
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Lines
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Entries
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Depth
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Minified chars
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Share risk
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Top-level keys

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Path preview

    Value mix

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    Before sharing

      Receiver shape

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      This formatter validates strict JSON. It will not repair missing quotes, comments, trailing commas, or other JSON5-style syntax because guessing can change data meaning.
       
       
       
        
       
       
      Field notes
       
      Practical JSON formatting notes for API and config work
       
      JSON formatting looks simple until the data comes from a log line, webhook retry, copied browser response, or a build configuration file. This page is meant for quick inspection before the payload moves into code, documentation, support notes, or a bug report.
       
       
       
       
      When formatting helps
       
       
      Use a formatter when the important question is structure: which keys exist, which values are arrays, whether a value is null, and whether a nested object is in the place you expected. Pretty printing makes those relationships visible without changing the data.
      Minifying is useful for transport, but it is a poor review format. If a payload is going into a ticket, a pull request comment, or a support handoff, format it first and copy only the relevant fragment.
       
       
         
      • Check API responses before comparing them with documentation.
      • Review feature flag or app configuration files before committing them.
      • Spot copied trailing commas, comments, or single quotes that are valid in JavaScript but invalid in strict JSON.
      • Create a clean sample payload for a bug report without including private fields.
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      Strict JSON versus JavaScript object syntax
       
       
      This tool validates strict JSON, not JavaScript object literals. That distinction matters because many snippets copied from code contain comments, unquoted keys, undefined values, dates, or trailing commas. Those forms may run in a JavaScript file, but they are not valid JSON for an API body.
      When the parser reports an error, fix the source text rather than relying on a tool to guess. Automatic repair can silently turn a configuration mistake into a different payload.
       
        
       
       Node.js strict JSON check js 
       
      const raw = process.env.API_PAYLOAD || "{}";

try {
  const parsed = JSON.parse(raw);
  console.log(JSON.stringify(parsed, null, 2));
} catch (error) {
  console.error(`Invalid JSON: ${error.message}`);
}
       
       
       
      Large payload habits
       
       
      For very large payloads, format only the part you need to inspect. Browser-based formatting is convenient, but huge arrays and deeply nested logs can still make a page slow because the browser has to parse, allocate, and render the entire output.
      If the payload includes secrets, tokens, customer records, or internal identifiers, trim or redact it before using any online page. This site processes the formatter in the browser, but careful handling is still the safer workflow.
       
       
         
      • Redact access tokens, emails, phone numbers, and customer IDs before sharing output.
      • Collapse the problem to the smallest object that still reproduces the issue.
      • Use depth and top-level entry counts to decide whether the payload is small enough to review as one block.
      • Keep both formatted and minified versions only when the receiving system needs one-line JSON.
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      Common mistakes to check before copying
       
       
      A valid parse only proves the text is valid JSON. It does not prove the payload matches an API schema, has the right date format, or contains every required field. Treat formatting as the first review pass, then validate against the service contract if the payload is going into production code.
       
       
         
      • A string that looks like a number is still a string.
      • null and an omitted property often mean different things to APIs.
      • Arrays with one item can hide bugs that appear when multiple items arrive.
      • Timezone strings inside JSON still need separate date handling.
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      How to use this tool
       
         
      1. Paste or type your input into the tool.
        2.  
      2. Choose the action or option that matches your task.
        3.  
      3. Review the output before copying it into another app.
        4.  
       
      Notes
       
      Paste strict JSON or load a sample, then format, minify, or copy sorted-key JSON, see type, depth, top-level keys, path previews, value mix, share risk, sharing review checks, entry and size details, catch parse errors, and copy formatted, minified, path-report, structure-report, review, or error output.
       
      Inputs are processed in the browser for this static MVP. Avoid pasting secrets into any online tool unless you understand the environment.
       
        
      FAQ
      Does this JSON formatter upload my data?
      No. Formatting runs locally in your browser in this static version, but you should still avoid pasting secrets into any online page.
      Can it fix invalid JSON automatically?
      It reports parse errors, but it does not guess missing commas, comments, or quotes because automatic repairs can change the data meaning.
      What counts as valid JSON?
      Valid JSON can be an object, array, string, number, boolean, or null, but it cannot include trailing commas or JavaScript-style comments.
      When should I use minified output?
      Use minified output when you need a compact value for a config field, fixture, or API example after you have already reviewed the formatted version.
       
       
      Related Pages
       
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