What kinds of differences does the JSON diff detect?

The diff identifies added keys, removed keys, changed values (including type changes), and structural differences in nested objects and arrays.

Does key order matter when comparing JSON?

JSON objects are unordered by spec, so the diff compares by key name rather than position. Key order differences are not flagged as changes. Array order differences are flagged because arrays are ordered.

Can I compare very large JSON payloads?

Yes, within browser memory limits. For multi-megabyte payloads, comparison may take a moment. If performance is critical, consider comparing specific sub-sections of the JSON rather than the full document.

Compare Two JSON Objects Online

Comparing two JSON objects manually — looking for added keys, changed values, or removed fields — is error-prone and slow, especially in large payloads. Developers encounter this constantly: comparing API responses from two environments, reviewing configuration changes between deploys, checking that a data migration produced the expected output, or diffing two versions of a feature flag file. devtoolkit.sh's JSON Diff tool takes two JSON inputs and produces a clear, highlighted diff showing exactly what changed. Added keys appear in green, removed keys in red, and modified values are shown side by side so you can see the before and after at a glance. The JSON Formatter is also handy before diffing — if either input is minified, formatting it first makes the diff output easier to read. The diff runs entirely in your browser, so you can safely compare JSON containing internal configuration, API keys, or user data without any privacy concerns.

{}JSON DiffHOT

Compare two JSON objects and highlight added, removed, and changed keys.

{}JSON FormatterHOT

Pretty-print and format JSON with proper indentation.

FAQ

What kinds of differences does the JSON diff detect?: The diff identifies added keys, removed keys, changed values (including type changes), and structural differences in nested objects and arrays.
Does key order matter when comparing JSON?: JSON objects are unordered by spec, so the diff compares by key name rather than position. Key order differences are not flagged as changes. Array order differences are flagged because arrays are ordered.
Can I compare very large JSON payloads?: Yes, within browser memory limits. For multi-megabyte payloads, comparison may take a moment. If performance is critical, consider comparing specific sub-sections of the JSON rather than the full document.