Download Excel File From Byte Array Javascript [better] [ 2026 Release ]

: Create a hidden anchor ( ) element, set its href to the temporary URL and its download attribute to the desired filename, then programmatically "click" it. Clean Up : Revoke the temporary URL to free up memory. Implementation Example

: Use application/vnd.openxmlformats-officedocument.spreadsheetml.sheet for .xlsx or application/vnd.ms-excel for .xls . Libraries : For broader support, use FileSaver.js .

: Create a new Blob object from your byte array, specifying the correct MIME type for Excel. download excel file from byte array javascript

To download an Excel file from a byte array in JavaScript, you generally follow these four steps:

Below is a standard JavaScript function that handles this process. javascript : Create a hidden anchor ( ) element,

// Creates a Blob from binary data and triggers download function downloadExcelFromBytes(byteArray, fileName) { const blob = new Blob([byteArray], { type: 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet' }); const url = window.URL.createObjectURL(blob); const link = document.createElement('a'); link.href = url; link.setAttribute('download', fileName); document.body.appendChild(link); link.click(); document.body.removeChild(link); window.URL.revokeObjectURL(url); // Free memory } Use code with caution. Key Considerations

: If the backend sends a Base64 string, decode it into a Uint8Array first. Libraries : For broader support, use FileSaver

In web development, a common requirement is to receive a file from a backend API in raw binary format (a byte array) and trigger a download in the user's browser. For Excel files ( .xlsx or .xls ), this involves converting that binary data into a format the browser can handle—typically a —and then using a temporary link to initiate the download. Core Steps to Download an Excel Byte Array