Convert XLS to YAML Online Free

Convert legacy Excel XLS spreadsheets to YAML configuration format. Each row becomes a YAML mapping with column headers as keys — useful for extracting config data from older Excel files into modern YAML workflows.

By ChangeThisFile Team · Last updated: March 2026

Quick Answer

ChangeThisFile converts your legacy XLS spreadsheet to YAML on our server using SheetJS and js-yaml. Column headers become YAML keys and each row becomes a YAML mapping. Free, no signup required, file deleted immediately after conversion.

Free No signup required Encrypted transfer · Auto-deleted Under 2 minutes Updated April 2026

Convert XLS to YAML

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Drag & drop your .xls file here, or click to browse

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XLS vs YAML: Format Comparison

Key differences between the two formats

FeatureXLSYAML
Format typeLegacy binary spreadsheet (BIFF)Plain text, indentation-based
AgeIntroduced 1987, legacy formatModern, widely used for config
ReadabilityBinary — requires spreadsheet appHuman-readable in any text editor
CompatibilityWide but aging supportUniversal across dev tools and pipelines
Data typesExcel types (dates, numbers)String, int, float, boolean, null
Version controlBinary diffs unreadableLine-level diffs in Git
Config toolingNot applicableKubernetes, Helm, Ansible, GitHub Actions

When to Convert

Common scenarios where this conversion is useful

Migrate legacy config data to YAML

Extract configuration tables from old XLS files — common in enterprise environments — and migrate them to YAML for use in modern CI/CD and deployment tools.

Archive and modernize old spreadsheets

Convert XLS archives to YAML for long-term storage in version control. YAML is plain text, diff-friendly, and readable without proprietary software.

DevOps data preparation

Transform server or environment inventory XLS files into YAML for Ansible inventory files or environment variable definitions.

Test fixture extraction

Convert legacy XLS test case files to YAML fixtures for modern test frameworks. Preserve your existing test data while updating the format.

How to Convert XLS to YAML

  1. 1

    Upload your XLS file

    Drag and drop your .xls file or click to browse. The first sheet in the workbook is used.

  2. 2

    Server converts to YAML

    Your file is sent securely to our server. SheetJS reads the XLS binary format and js-yaml writes each row as a YAML mapping. Deleted immediately after.

  3. 3

    Download the YAML result

    Click Download to save your .yaml file. The output is a YAML list of mappings with column headers as keys.

Frequently Asked Questions

XLS is the older binary format used by Excel 97-2003. XLSX is the newer XML-based format introduced in Excel 2007. Both are converted to the same YAML structure.

The first row of your XLS spreadsheet becomes the YAML mapping keys. Each subsequent row creates a YAML mapping with those keys and the cell values.

Yes. Numeric cells become YAML numbers, boolean-looking cells become YAML booleans, and text cells become YAML strings. Dates become ISO 8601 formatted strings.

The converter reads cell values only. Macros and VBA code are ignored. If your XLS relies on macros to compute values, make sure the cells show their calculated results before uploading.

The first (leftmost) sheet is converted. Rearrange the tabs in Excel to control which sheet is processed.

Empty cells are omitted from each YAML mapping. Only cells with values generate keys in the output.

XLS files support up to 65,536 rows and 256 columns. The converter handles the full XLS row limit. For very large files, conversion may take a few seconds longer.

Yes. Your XLS file is uploaded over encrypted HTTPS, converted on our server, and deleted immediately after you download the YAML result.

Yes. Use the XLS to JSON or XLS to CSV converters for other output formats. The same SheetJS-based parsing is used for all XLS conversions.

No. The conversion runs entirely on our server using SheetJS, which parses XLS files without any Office installation.

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Need to convert programmatically?

Use the ChangeThisFile API to convert XLS to YAML in your app. No rate limits, up to 500MB files, simple REST endpoint.

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