Q: Why does my JSON fail to parse when it works in JavaScript?
JavaScript object literals and JSON look similar but are not the same language. JSON requires double-quoted keys, double-quoted strings, no trailing commas, and no comments. If you copy-pasted from a JS source file, you almost certainly tripped one of those rules. Beautifying surfaces the exact spot.
Q: My API returns 64-bit integers as numbers. Why do they round?
JavaScript stores all numbers as IEEE 754 double-precision floats, which only safely represent integers up to 2^53 - 1 (about 9 quadrillion). Twitter snowflake IDs, Discord IDs, and any 64-bit int past that limit silently lose precision when parsed. The fix on the producer side is to serialize them as strings. The formatter shows them as-is, so the rounding may already have happened upstream.
Q: Is the tool sending my JSON to a server?
No. Parsing and formatting run entirely inside your browser's JavaScript engine. Open DevTools → Network and you'll see no outbound request when you paste, beautify, or minify. That makes it safe for payloads from internal staging APIs, authenticated responses, or anything you would not upload to a public converter.
Q: How big a file can the formatter handle?
There's no hard cap, but practical limits are set by the device. A modern desktop browser handles 5–10 MB without trouble. Past 25 MB the editor itself starts lagging; past 100 MB the tab usually runs out of memory. For one-off jobs that large, pipe the file through jq . in a terminal instead.
Q: Can the formatter sort keys alphabetically?
The default behaviour preserves insertion order, since the JSON spec does not mandate key ordering and some consumers depend on the original sequence (signed payloads, canonical JSON, etc.). If you need sorted output, run jq --sort-keys . on the file before pasting, or post-process the beautified result.
Q: Does the validator follow a particular JSON standard?
Yes — RFC 8259, which is the current JSON standard. That means UTF-8 by default, double-quoted strings, no comments, no trailing commas, and no unquoted keys. If you need superset syntax (comments, trailing commas), look at JSON5 instead — but you'll need a JSON5 parser downstream too.