Cast Column Types in Excel Files Online
Change column data types in Excel files directly in your browser. Cast text to numbers, dates to timestamps, or any supported type conversion — no upload required.
About this tool
Change the data types of columns in a Excel file — cast text to integers, strings to dates, floats to booleans, and more. Uses TRY_CAST for safe conversion so invalid values become null instead of causing errors. All processing in your browser.
Frequently Asked Questions
What types can I cast columns to in a Excel file?
VARCHAR (text), INTEGER, BIGINT, FLOAT, DOUBLE, BOOLEAN, DATE, and TIMESTAMP. The tool uses TRY_CAST for safe conversion — values that cannot be converted become null.
Can I cast multiple columns at once in a Excel file?
Yes. Set a target type for each column you want to change. Columns left as "Keep original" are passed through unchanged.
What happens to values that cannot be converted?
They become null. TRY_CAST never fails — it returns null for any value that does not fit the target type. Check the preview for unexpected nulls before downloading.
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.
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