Combine Columns in YAML Files Online

Combine multiple columns into one in YAML files directly in your browser. Merge first name and last name, join address fields, or concatenate any columns with a custom separator — no upload required.

How to combine Columns in YAML files

Drop your file onto the upload area. The first two columns are ticked by default and the output name is set to both names joined by an underscore.
Tick the columns to combine in the order you want them joined. Each ticked column shows its position (#1, #2, and so on), and the order follows your clicks, not the file's column order.
Type the separator, such as a space, ", " or " - ", and set the output column name.
Tick Remove source columns if you only want the combined column, then click Combine Columns.
Check the preview and download the file in the same format.

Your file is processed locally in your browser and is never uploaded. The free limit is 50 MB per file; larger files work if your device has the memory for them.

Worked example

An international order export stores the delivery address across four columns. The courier's upload form wants one address line per parcel.

Input (YAML)

- recipient: Priya Shah
  street: 12 Cuba Street
  city: Wellington
  postcode: '6011'
  country: New Zealand
- recipient: Tom Walsh
  street: 8 Quay Road
  city: Cork
  postcode: null
  country: Ireland
- recipient: Ines Duarte
  street: Rua Augusta 40
  city: Lisboa
  postcode: 1100-048
  country: Portugal

Settings

Columns, in click order: street, city, postcode, country
Separator: ", "
Output column name: full_address
Remove source columns: ticked

Result

recipient	full_address
Priya Shah	12 Cuba Street, Wellington, 6011, New Zealand
Tom Walsh	8 Quay Road, Cork, Ireland
Ines Duarte	Rua Augusta 40, Lisboa, 1100-048, Portugal

Values are joined in the order the columns were ticked, with the separator between them. Tom's postcode is empty, and it is skipped along with its separator, so there is no ", ," gap. With the source columns removed, full_address takes the position of the last source column. Unticked columns such as recipient stay where they were.

Frequently Asked Questions

What happens to empty (null) values when combining columns?

They are skipped, and so is the separator next to them. Combining "Cork", null and "Ireland" with ", " gives "Cork, Ireland". Empty strings are not null, so they are joined as-is.

Can I combine more than two columns, and control the order?

Yes. Tick as many columns as you need. They are joined in the order you tick them, shown as #1, #2 and so on next to each column name.

Can I leave the separator empty?

Yes. With an empty separator the values are joined directly, for example "AB" and "123" become "AB123".

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