JSON cross join rows
ClientPair every row from A with every row from B—Cartesian product fixtures for test matrices (watch output size).
Learn more: JSON cross join
Build the Cartesian product of two JSON row arrays—every row from A paired with every row from B—for test matrices, combination fixtures, and exhaustive pairing checks.
Output size
Row count multiplies: |A| × |B|. Large inputs can produce huge arrays and slow the tab—start with small samples to verify shape before scaling.
Merged row shape
Each output row typically merges fields from both sides. Rename conflicting keys in source data if you need predictable column names in the result.
Privacy
Cross join executes in your browser on pasted JSON only.
About JSON cross join rows
Pair every row from A with every row from B—browser. Parsing and transforms run in your browser—Toolcore does not upload your JSON for this operation.
How to use
Paste a JSON array (or follow the two-array example on join tools). Use Load example when shown, or prefill with ?q= / ?qb= on the tool URL.
Input and limits
Fix JSON syntax errors before expecting output. Very large arrays may slow the tab—trim samples during exploration, then scale up locally.
Nearby workflows on Toolcore
- JSON formatter — JSON format online: pretty-print, minify, validate, escape, download . Useful once JSON parses on this page.
- JSON replace values — Replace every value equal to from with to—use from|to, JSON or plain text. Useful once JSON parses on this page.
- JSON filter field by regex — Keep rows whose string field matches a regular expression—local. Useful once JSON parses on this page.
- JSON count field nulls — Count null or missing values for one row field—metadata. Useful once JSON parses on this page.
Common use cases
- Build every combination of two small row sets for test matrices or cartesian fixtures.
- Expand product × region JSON samples for chart grid testing.
- Generate exhaustive pairing data without a spreadsheet cartesian product formula.
Common mistakes to avoid
Cross joining large arrays
Output size is |A|×|B|—start with tiny samples to avoid freezing the tab.
Colliding field names on merge
Rename keys on one side if merged rows overwrite fields unexpectedly.
Using cross join when you meant union
Union all stacks arrays; cross join pairs every row with every row.
FAQ
Where does cross join run?
In your browser on pasted JSON.
Can agents prefill?
Yes—for the JSON input via ?q= or ?qb=.
What is the output shape?
An array of merged rows—one for each pair from A and B.
More tools
Related utilities you can open in another tab—mostly client-side.
JSON formatter
ClientJSON format online: pretty-print, minify, validate, escape, download .json.
JSON replace values
ClientReplace every value equal to from with to—use from|to, JSON or plain text.
JSON filter field by regex
ClientKeep rows whose string field matches a regular expression—local.
JSON count field nulls
ClientCount null or missing values for one row field—metadata.