All tools

Base64 to Excel Decoder

Decode a Base64 string and download as an Excel spreadsheet. Free and private.

Length: 0 characters

Leave as-is unless you know the original file type. Data URIs auto-detect.

Base64 to Excel decodes a Base64 string back into an XLSX or XLS spreadsheet file. ConvertDa's free Base64 to Excel tool runs in your browser — paste the string and download the working spreadsheet in seconds.

How to base64 → excel

  1. 1

    Paste your Base64 string.

  2. 2

    Click Decode & Download.

  3. 3

    Open the .xlsx in Excel, Numbers, or LibreOffice.

Frequently asked questions

Can I decode to CSV instead?▾

Yes — change the filename extension to .csv before downloading.

Does it preserve formulas in the decoded file?▾

Yes. Base64 decoding restores the exact bytes of the original spreadsheet, including formulas, formatting, and embedded charts.

Why does Excel show 'file format invalid' when I open the result?▾

Usually because the source Base64 string was incomplete. Re-copy the full string and decode again. Also confirm you picked the right output format (XLSX vs XLS).

Related tools

Base64
Encode any text to Base64 or decode Base64 back to text. Runs entirely in your browser.
File → Base64
Encode any file to a Base64 string in your browser. Useful for data URIs, APIs, and email attachments.
Base64 → File
Decode a Base64 string and download the original file. Runs entirely in your browser.
PDF → Base64
Convert a PDF to a Base64 string in your browser. Useful for embedding PDFs in JSON or email APIs.
Base64 → PDF
Decode a Base64 string and download a PDF file. Browser-based, fully private.
Word → Base64
Convert a Word .docx file to a Base64 string. Runs in your browser.