INI Formatter & Validator

How it works

• Format re-serializes with normalized key = value spacing and quoting, while keeping your [section] headers, comments, and blank lines exactly where they were.
• To JSON nests keys under their [section], and a dotted section path like [servers.alpha] nests further — the same convention this site’s TOML formatter uses for dotted tables.
• Handles top-level keys before any section header, key: value as an alternate to key = value, double-quoted values with \n/\r/\"/\\ escapes, single-quoted literal values, and full-line ; or # comments.
• To JSON only infers numbers and booleans from an unquoted value — a quoted "true" or "123" always comes out as a JSON string, the same way quoting works as an explicit “force string” escape hatch in YAML and TOML.
• Reopening the same [section] merges into it rather than erroring — plain INI has no rule against splitting one section’s keys across two blocks, unlike this site’s TOML formatter, where redefining a [table] is a hard error because TOML’s own spec forbids it.

A duplicate key within the same section doesn’t block Format or To JSON — the last definition wins, and you’ll see a note above the output naming both lines. A key colliding with an existing section name (or vice versa) is a different, structural kind of problem and IS a hard error everywhere — that’s not a style risk, it’s two incompatible things trying to occupy the same name. There’s also no support for an inline/trailing comment after a value (key = value ; note) — classic INI has no comment-escaping convention for that position, so the ; and everything after it is just read as part of the value, not stripped.

Runs entirely in your browser — nothing you paste here is uploaded, logged, or stored.