Updated Developer & API Tool

JSON Formatter

Pretty-print, minify and validate JSON in one place. Detect syntax errors with line and column hints, sort object keys, customize indentation and copy clean JSON for APIs, logs and configuration files.

Pretty Print Minify JSON Validation & Errors Key Sorting

Format, Minify and Validate JSON

Paste raw JSON, choose your indentation and optional key sorting, then format or minify it. The JSON Formatter highlights parse errors with approximate line and column positions so you can quickly fix issues in API responses, log files or configuration objects.

The formatter expects valid JSON (double-quoted keys and strings). For JavaScript objects with single quotes or trailing commas, adjust them to standard JSON first.

Sorting keys can make large configuration files easier to diff and compare, but it may change the order of properties relative to the original JSON.

Minify JSON by removing all unnecessary whitespace and line breaks, producing a compact one-line string ideal for embedding in code, URLs, or small config files. The minifier also validates the JSON before generating output.

JSON Formatter Calculator – Pretty Print, Minify and Validate JSON

The JSON Formatter Calculator on MyTimeCalculator is built for developers, data engineers and analysts who work with JSON every day. It helps you quickly pretty-print raw JSON, detect syntax errors, minify large payloads and generate clean, copy-ready output for APIs, logs, configuration files and documentation.

JSON (JavaScript Object Notation) is a lightweight text format for structured data. Its simplicity makes it the default choice for web APIs, microservices and configuration files, but even small mistakes like missing commas or quotes can break entire responses. A reliable formatter and validator saves time and prevents subtle bugs.

1. What Does the JSON Formatter Do?

This JSON Formatter focuses on three main tasks:

  • Pretty printing: Re-formatting valid JSON with consistent indentation and line breaks so it is easier to read and review.
  • Minification: Removing extra whitespace, tabs and line breaks to create a compact one-line representation of the same JSON structure.
  • Validation: Checking whether the input is valid JSON and showing an error if it is not, including approximate line and column hints.

Because the calculator uses standard JSON parsing, it works with the same rules used by browsers and many programming languages.

2. How to Use the JSON Formatter Calculator

  1. Paste your JSON: Copy any JSON string from your code, log files or API responses and paste it into the main input box.
  2. Choose indentation: Select the number of spaces you want for each indentation level (2, 4, 1 or no extra indentation).
  3. Optionally sort keys: If you enable key sorting, the formatter will output objects with their keys arranged alphabetically. This is useful for comparing configurations or versioning data.
  4. Click “Format JSON” or “Validate Only”: The tool will parse your JSON, display any errors and show the formatted version when parsing succeeds.
  5. Use the “Minify” tab if needed: When you need a compact representation, switch to the “Minify & Compact” tab and click “Minify JSON” to generate a one-line output.

You can use the copy buttons on each output to quickly reuse cleaned JSON in code editors, terminals or other tools.

3. Understanding JSON Validation and Error Messages

When the JSON is invalid, the formatter shows a message describing the problem and an approximate line and column where the parser stopped. Common issues include:

  • Single quotes instead of double quotes around keys or strings.
  • Trailing commas after the last item in an array or object.
  • Missing commas between object properties or array elements.
  • Unquoted keys or reserved words being used as keys without quotes.

The error location is based on the character position reported by the JSON engine. The calculator converts this position to a line and column estimate so you can jump directly to the likely problem in your editor.

4. When to Pretty Print vs Minify JSON

Pretty-printed JSON is ideal when humans need to read, debug or review the data:

  • Inspecting API responses in development.
  • Reviewing configuration files during code reviews.
  • Exploring nested objects or arrays to understand schemas.

Minified JSON is better when bandwidth and storage are more important than readability:

  • Sending payloads over a network where every byte matters.
  • Embedding JSON into HTML attributes, URLs or small configuration blobs.
  • Storing large datasets where whitespace would significantly increase size.

5. Limitations and Best Practices

The JSON Formatter follows the official JSON specification, which means it:

  • Requires double quotes around keys and string values.
  • Does not allow comments, trailing commas or unquoted keys.
  • Does not execute any code or handle JSON5 or JavaScript object literal extensions.

To convert non-standard JSON-like content (for example, JavaScript objects with comments or single quotes), adjust them to valid JSON syntax before using the formatter. This keeps behavior predictable and consistent with production JSON parsers.

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JSON Formatter Calculator FAQs

Frequently Asked Questions

Quick answers to common questions about formatting, minifying and validating JSON with this calculator.

Some programming languages and frameworks support JSON-like object literals that are not strictly valid JSON, such as single quotes, comments or trailing commas. The JSON Formatter uses strict JSON rules, similar to JSON.parse() in JavaScript. If your data relies on non-standard extensions, convert it to valid JSON syntax before formatting or validation.

When key sorting is enabled, the formatter rebuilds each JSON object with its keys in alphabetical order. This does not change the underlying values but can change the textual representation, which makes diffs and comparisons more predictable. Keep it off if the original property order carries meaning in your specific use case or if you want to preserve the exact order from an API response.

No. The formatter parses your JSON into a data structure and then serializes it back to text using the same numeric and boolean values. Only whitespace, indentation and key order (if sorting is enabled) are changed. Strings, numbers, booleans and null remain semantically identical to the original input as long as the JSON is valid.

The practical limit depends on your browser and device memory rather than a hard limit in the calculator itself. Very large JSON documents may take longer to parse and format and could slow down the page. For extremely large datasets, consider streaming or chunk-based tools designed specifically for big JSON processing.

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