JSON Diff Tool
without reorder noise.
JSON diffs get noisy when package-style or application settings files reorder nested objects before a release.
DiffViewr uses Template A as the source of truth, aligns Target B to that structure, and keeps strict JSON validation in front of the comparison.
Client-side compare. No upload. Duplicate keys blocked before review.
{ "name": "@acme/checkout-api", "version": "2.4.0", "scripts": { "start": "node server.js", "worker": "node worker.js" }, "config": { "api": { "baseUrl": "https://staging-api.acme.test", "timeoutMs": 5000 },Comments, trailing commas, and JSON5 syntax are rejected so the comparison matches production parsers.
Duplicate object keys are invalid only within the same object scope.
Deep settings changes are easier to inspect after key order is normalized.
FAQ
JSON comparison details
Does the JSON comparer support comments or trailing commas?
No. DiffViewr validates strict JSON, so JSONC, JSON5, comments, and trailing commas are invalid.
Are duplicate JSON keys allowed if the browser parser keeps the last value?
No. DiffViewr checks for duplicates before parsing and marks the file invalid when the same key appears twice in one object.
Can the same key appear in two different nested JSON objects?
Yes. Scope matters for JSON. A key repeated in separate nested objects is valid.
Does array order matter?
Array values are not treated as duplicate keys. You can also enable the array reorder option when you want Target B arrays aligned to Template A.
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