What is valid JSON syntax?

JSON is text built from objects `{}`, arrays `[]`, strings in double quotes, numbers, `true`, `false`, and `null`. Keys must be double-quoted strings; trailing commas, single-quoted strings, and unquoted keys are invalid in strict JSON (even if JavaScript tolerates some of them).

Why does my JSON fail to parse with a vague error?

Common culprits are trailing commas after the last property, smart quotes from word processors, BOM at file start, mixing single quotes, or embedding unescaped control characters. Paste into a formatter to locate the first structural break; many errors are one character before the reported position.

Should I minify or beautify JSON for production?

Minify (compact, no extra whitespace) for wire transfer and static assets to save bytes. Beautify for configs you edit by hand, code review, and debugging. APIs often minify responses; humans use pretty-printed copies in repos and docs.

How is JSON different from YAML?

JSON is a strict, ubiquitous interchange format with explicit delimiters. YAML trades braces for indentation and adds features like anchors and multi-line scalars. Use JSON for APIs and browser-native parsing; YAML is common for Kubernetes and CI configs. Convert both ways with the [JSON to YAML](/json-yaml) tool when you need the other shape.

What is JSON Schema and does formatting affect it?

JSON Schema describes allowed structure and types for JSON documents. Formatting (whitespace, key order) does not change semantic validity of the data, but invalid JSON cannot be validated until it parses. Fix structure first, then validate against your schema in your toolchain.

JSON Formatter

v1.2.0

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Frequently Asked Questions

What is valid JSON syntax?: JSON is text built from objects `{}`, arrays `[]`, strings in double quotes, numbers, `true`, `false`, and `null`. Keys must be double-quoted strings; trailing commas, single-quoted strings, and unquoted keys are invalid in strict JSON (even if JavaScript tolerates some of them).
Why does my JSON fail to parse with a vague error?: Common culprits are trailing commas after the last property, smart quotes from word processors, BOM at file start, mixing single quotes, or embedding unescaped control characters. Paste into a formatter to locate the first structural break; many errors are one character before the reported position.
Should I minify or beautify JSON for production?: Minify (compact, no extra whitespace) for wire transfer and static assets to save bytes. Beautify for configs you edit by hand, code review, and debugging. APIs often minify responses; humans use pretty-printed copies in repos and docs.
How is JSON different from YAML?: JSON is a strict, ubiquitous interchange format with explicit delimiters. YAML trades braces for indentation and adds features like anchors and multi-line scalars. Use JSON for APIs and browser-native parsing; YAML is common for Kubernetes and CI configs. Convert both ways with the [JSON to YAML](/json-yaml) tool when you need the other shape.
What is JSON Schema and does formatting affect it?: JSON Schema describes allowed structure and types for JSON documents. Formatting (whitespace, key order) does not change semantic validity of the data, but invalid JSON cannot be validated until it parses. Fix structure first, then validate against your schema in your toolchain.