Free Tools /Development
JSON Diff Checker
Paste two JSON blobs to see exactly what was added, removed, or changed, including inside nested objects and arrays.
- Free, no signup
- Runs in your browser
- Nothing stored
How this tool works
Deep, key-by-key comparison
Recursively walks both JSON objects and reports every key that was added, removed, or changed in value, including inside nested objects and arrays.
Type-aware
Flags a value that changed type (a string "490" versus a number 490) separately from a value that simply changed, since that distinction is often the actual bug in a broken workflow.
No context needed
Works on any two JSON blobs, an API response before and after a vendor update, two executions of the same n8n node, or a config file diff.
Frequently asked questions
Why did my n8n workflow start failing after an API update with no visible error?
This is the single most common use case for this tool: a third-party API silently renamed a field, changed a value from a number to a string, or nested a field one level deeper. A downstream node referencing the old path returns undefined instead of throwing a clear error.
Does key order matter in the comparison?
No, keys are compared by name regardless of their order in the object, matching how JSON.parse and virtually every consumer of JSON treats objects (order-independent for object keys, though order does matter for arrays).
How are arrays compared?
Arrays are compared index by index. If array lengths differ, the extra items in the longer array are reported as added or removed. This is a positional comparison, not a "did this item exist somewhere in the array" comparison.
Can I compare more than two JSON blobs at once?
No, this tool compares exactly two inputs at a time. For comparing more than two versions, run the tool pairwise between consecutive versions.
Does this tool store either JSON blob?
No, the comparison runs entirely in your browser. Neither input is transmitted or saved anywhere.
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