YAML to Excel Converter

Convert YAML to Excel without a CSV detour

Opening CSV files in a spreadsheet invites problems: the app guesses the delimiter, may turn long numbers into scientific notation and can reinterpret date-like text. This YAML to Excel converter skips that step and builds a genuine .xlsx workbook in your browser, with one row per YAML record and a column for every field.

Example

- id: 1
  name: Ava Martinez
  plan: Pro
  address:
    city: Denver
    country: US
- id: 2
  name: Noah Kim
  plan: Free
  address:
    city: Seoul
    country: KR

After Convert to Excel, the preview shows the sheet contents as CSV:

id,name,plan,address.city,address.country
1,Ava Martinez,Pro,Denver,US
2,Noah Kim,Free,Seoul,KR

The status bar confirms something like Excel workbook ready (1 sheet, 8.7 KB) — click Download. The download is an Excel file, not the CSV you see in the preview.

What the workbook contains

• One sheet, named with the Sheet name option (default Sheet1). The exception: if the top level is a mapping whose values are all lists of records, such as users: and teams:, each list gets its own sheet named after its key.
• A header row with the field names, followed by one row per record.
• Typed cells. Numbers and booleans from YAML are stored as numbers and booleans, so formulas like SUM work immediately. Strings stay text, including quoted values like "00123".
• Sized columns. Column widths are set from the longest value in each column (up to a sensible maximum), so the sheet is readable when it opens.

Nested data and flattening

Flatten nested objects is on by default: nested mappings become columns like address.city, and list items get numbered columns like tags.0 and tags.1. If you untick it, each nested value is placed in a single cell as JSON text, which keeps the column count small when lists are long.

The converter looks for the list of records in your YAML. A top-level list is used directly; a mapping that wraps one list of records (for example customers: followed by items) uses that list; any other mapping becomes a single row.

Typical uses

• Handing a YAML inventory, such as servers, feature flags or translation keys, to colleagues who work in Excel.
• Reviewing test fixtures or seed data with filters and sorting instead of scrolling through indentation.
• Preparing a bulk upload for a system whose import screen only accepts spreadsheets.

If you edit the workbook and later need the data back in YAML, save the sheet as CSV and run it through the CSV to YAML converter. Dot-notation headers can be turned back into nested keys there.

Sheet name rules

Excel limits sheet names to 31 characters and does not allow \ / ? * [ ] :. The converter removes those characters and shortens long names automatically, and falls back to Sheet1 if nothing is left.

When to use a different tool

• For a plain text file that any program can read, use YAML to CSV.
• To look at the data as a table without downloading anything, try the YAML viewer.
• If your data is in JSON rather than YAML, JSON to Excel produces the same kind of workbook.

Privacy

The workbook is generated in your browser with a JavaScript spreadsheet library, and your YAML is not uploaded. Our server is only involved if you use Load URL or Save & Share.