Unpivot JSON Files Online

What does unpivoting a JSON file mean?

Unpivoting (also called melting) reshapes a wide table into a long one. Columns you select as "value columns" are stacked into two new columns — one for the original column name and one for the value. ID columns are repeated on every row.

When would I unpivot a JSON file?

When you have data spread across columns — like monthly sales in Jan, Feb, Mar columns — and need it in long format with a "month" column and a "sales" column. Long format is required by most charting libraries and tidy-data workflows.

Can I reverse an unpivot (pivot from long to wide)?

Yes — use the Pivot tool to go from long to wide format. Together, unpivot and pivot let you reshape data in both directions.

Is my data private?

Yes — completely. Your file is never uploaded to any server. Everything runs locally in your browser using WebAssembly — processing happens entirely inside your tab. Once you close the tab, nothing is retained.

What is the maximum file size?

The free limit is 50 MB. For larger files, performance depends on your device's available memory — most modern machines handle 500 MB to 1 GB comfortably.