Question 1

Does the comparison care about key order, or only values?

Accepted Answer

Only values and structure — reordering keys within an object never shows up as a change, since object key order has no meaning in JSON. Only additions, removals, and value changes are reported.

Question 2

How are changes inside arrays detected — by position, or by matching similar items?

Accepted Answer

By position (index): item 0 on the left is compared against item 0 on the right, item 1 against item 1, and so on. This is simple and predictable, but it means inserting a new item at the start of an array will show every item after it as "changed" — since everything shifted by one position — rather than a single clean "item added." Worth keeping in mind when diffing reordered lists.

Question 3

Can I hide fields that are identical on both sides?

Accepted Answer

Yes — there's a toggle to show only additions, removals, and changes, hiding unchanged fields so a small diff in a large document doesn't get lost. It's on by default.

Question 4

Is this useful for comparing API responses between staging and production?

Accepted Answer

That's one of the most common uses — paste the staging response on one side and production on the other to catch drift (a field that's missing, renamed, or has a different type) before it causes a bug. Since the diff is structural rather than text-based, differently-formatted-but-equivalent JSON on each side won't produce false positives.

JSON Compare

Structural Diff

Handles Large Documents

Local Processing

Frequently Asked Questions