How to transpose a json array of objects into a pivot table
- Step 1Ensure the JSON array is consistently structured — Transposing works best when all objects have the same keys. Use the JSON Null Stripper or JSON Key Filter to normalize the array first if some records have optional fields.
- Step 2Paste the row-oriented JSON array — Paste an array like [{ "month": "Jan", "revenue": 1000, "cost": 600 }, { "month": "Feb", "revenue": 1200, "cost": 700 }].
- Step 3Apply the transpose — Click Transpose. The output is: { "month": ["Jan", "Feb"], "revenue": [1000, 1200], "cost": [600, 700] }.
- Step 4Feed into a chart or pivot library — Pass the transposed object to Chart.js (where each key's array is a dataset), or to PivotTable.js by converting back to the expected input format. For Apache Arrow, each column array becomes an Arrow vector.
Frequently asked questions
How is a transposed JSON object different from a pivot table?+
Transposing produces a column-array map — one array per field across all rows. A pivot table further aggregates values — summing revenue by category, counting orders by status. The transposed JSON is the intermediate format used as input to a pivot aggregation step.
How do I transpose back from column arrays to row objects?+
Use the JSON Transposer again — the tool is its own inverse. Alternatively, in JavaScript: const rows = columnData.month.map((_, i) => Object.fromEntries(Object.entries(columnData).map(([k, v]) => [k, v[i]]))); This zips the column arrays back into row objects.
Is the data transmitted to JAD Apps?+
No. Transposition runs entirely in your browser. Data arrays and analytics records are never transmitted to JAD Apps servers.
Privacy first
Conversion runs locally in your browser. No file is uploaded — only metadata counters are saved for signed-in dashboard stats.