Single quotes
JSON: String values and keys must use double quotes.
JSON5: Single quotes are allowed in many cases.
JSON vs JSON5: Syntax Differences
Compare comments, quotes, trailing commas and keys. Toolbye validates strict JSON; it does not parse or automatically convert JSON5.
Core differences between JSON and JSON5
Comments
JSON: Comments are not part of the standard.
JSON5: Inline and block comments are supported.
Trailing commas
JSON: A trailing comma makes the payload invalid.
JSON5: Trailing commas are allowed.
Quoted keys
JSON: Object keys must be wrapped in double quotes.
JSON5: Unquoted identifier-like keys are allowed.
Why these differences cause validation errors
Many tools, APIs, and backends use strict JSON parsing, not JSON5 parsing.
- When a parser follows strict JSON rules, JSON5-only syntax is rejected immediately.
- JavaScript-like convenience syntax can look normal in code, but still be invalid as data exchange JSON.
- Fix the first reported error position first; later errors are often side effects.
When you should use standard JSON
- API request and response payloads that need predictable parsing across services.
- Data exchange between systems, teams, and languages where strict interoperability matters.
- Configuration files consumed by tools that expect strict JSON only.
FAQ: JSON vs JSON5
Is JSON5 a replacement for JSON?
No. JSON5 is a more flexible format, but many systems still require strict standard JSON.
Why does my config work locally but fail in an API?
Local tooling may accept JSON5 syntax, while the API parser often accepts strict JSON only.
How can I convert JSON5-style content to standard JSON?
Toolbye does not convert JSON5. Use a JSON5 parser for full conversion, or manually correct the syntax shown here and validate the result as strict JSON.
Where can I check if my content is strict JSON?
Use the main Toolbye JSON tool to validate and format the payload with strict parsing.
Related pages
JSON Formatter & Validator
Return to the main tool to validate strict JSON content now.
How to Find and Fix JSON Syntax Errors
Use these short examples to understand quotes, commas and bracket errors. The validator locates syntax problems; you make the corrections yourself.
JSON Validator Online: Check Syntax Errors
Paste JSON below to check syntax and locate errors by line and column. Correct the input yourself, then copy or download the formatted result.
JSON Minifier Online: Compact JSON
Paste valid JSON below to produce a compact result. Syntax is checked before output; copy or download the result in this workspace.