CSV to YAML converter

CSV to YAML turns each parsed CSV row into one YAML sequence item, with multiline fields written as block scalars when the YAML writer chooses that style.

Converted with Table engine · nothing stored
Free: 5 conversions a day · 5 MB each
Higher limits →

From real runs

What you get — and what changes

Element	Result	What happens
Row shape	Changed	Each CSV record became one item in a YAML sequence keyed by the CSV headers.
Multiline notes	Changed	The note line one and line two was serialized as a YAML block scalar with the \|- indicator.
Empty cells	Changed	Blank CSV cells became null in YAML, including the missing cells from the ragged final row.
Quoted thousands value	Kept	The quoted 1,234.50 amount stayed text in YAML because the comma prevented simple numeric inference.
Boolean values	Changed	true and false source strings became YAML booleans without quotes.
Date text	Changed	ISO-looking dates were emitted as full UTC timestamp values rather than the shorter source strings.

Row shape Changed
Each CSV record became one item in a YAML sequence keyed by the CSV headers.
Multiline notes Changed
The note line one and line two was serialized as a YAML block scalar with the |- indicator.
Empty cells Changed
Blank CSV cells became null in YAML, including the missing cells from the ragged final row.
Quoted thousands value Kept
The quoted 1,234.50 amount stayed text in YAML because the comma prevented simple numeric inference.
Boolean values Changed
true and false source strings became YAML booleans without quotes.
Date text Changed
ISO-looking dates were emitted as full UTC timestamp values rather than the shorter source strings.

Sample conversions

Block scalar note

Input: CSV row included "line one\nline two" in the note column and an empty trailing cell.
Output: YAML wrote note: |- followed by indented line one and line two, then empty: null for the blank cell.

Ragged record

Input: The final row was 003,Zoë with no remaining fields.
Output: YAML wrote id: 3, name: Zoë, and null for note, zip, active, amount, date, and empty.

A real CSV → YAML run

We converted our CSV sample (226 B) with Table engine on 2026-09-11. It took 2 ms and produced a 447 B YAML file, 2.0× larger than the input. The engine raised no warnings.

Input · sample.csv · 226 B

4 data rows × 5 columns; header: company,stage,arr,owner,close_date

Rows: 4
Columns: 5
Header: company,stage,arr,owner,close_date

Output · sample.yaml · 447 B

4 list items, 0 top-level keys, 20 lines

List items: 4
Top-level keys: 0
Lines: 20

First lines of the output

yaml

- company: Northwind Traders
  stage: Proposal
  arr: 48000
  owner: R. Ayers
  close_date: 2026-10-14T00:00:00.000Z
- company: Contoso Ltd
  stage: Negotiation
  arr: 120000
  owner: P. Ng
  close_date: 2026-09-30T00:00:00.000Z
- company: Fabrikam
  stage: Qualified
  arr: 22500
  owner: R. Ayers
  close_date: 2026-11-02T00:00:00.000Z
- company: Tailspin Toys
  stage: Won
  arr: 64000
…

Options and when to change them

delimiter: Set this when the CSV-like input uses semicolons, pipes, or tabs.
header: Keep it enabled for object-style YAML keyed by the first row; disable it for generated column names.
quote: Change the quote character only for a documented nonstandard CSV dialect.
encoding: Use latin1 for old exports before YAML is written, because YAML output is UTF-8 text.

Do it yourself

Python csv and PyYAML

bash

python - <<'PY'
import csv, yaml
with open("input.csv", newline="", encoding="utf-8-sig") as f:
    rows = list(csv.DictReader(f))
with open("output.yaml", "w", encoding="utf-8") as out:
    yaml.safe_dump(rows, out, allow_unicode=True, sort_keys=False)
PY

DictReader keeps blanks as empty strings unless you normalize them to None before dumping YAML.

CSV to YAML by API or MCP

The HTTP API and the MCP server run the exact engine this page uses (Table engine); the response carries the same warnings the web converter shows. Check support first with GET /api/v1/pairs?from=csv&to=yaml.

curl

curl -X POST https://filetypeconverters.com/api/v1/convert \
  -H "Authorization: Bearer $FTC_API_KEY" \
  -F "file=@input.csv" -F "from=csv" -F "to=yaml" \
  -F 'options={"delimiter":","}' \
  --output output.yaml

Options this engine accepts for CSV → YAML

Key	Applies to	Type	Default
delimiter	Reading CSV	string	,
header	Reading CSV	boolean	true
quote	Reading CSV	string	"
encoding	Reading CSV	utf-8 · latin1	utf-8
delimiter	Writing YAML	string	,
newline	Writing YAML	·
sheetName	Writing YAML	string
dialect	Writing YAML	postgres · mysql · sqlite	postgres
tableName	Writing YAML	string	data
createTable	Writing YAML	boolean	true

API reference

When this is the wrong conversion

Do not use YAML if the receiving system requires a declared schema or database-ready column types.
If leading zero identifiers must survive automatically, JSON from a text-preserving parser may be safer than this typed CSV path.

CSV to YAML questions

Why did CSV blanks become YAML null?

Our table engine maps blank cells to null before YAML serialization. That makes missing data explicit, but it differs from an empty string value.

How are multiline CSV fields written in YAML?

Our sample note became a block scalar using |-. That format keeps the line break readable while still representing one field.

Can CSV to YAML keep the original column order?

Yes for the rows we tested. The YAML writer followed the header order from the CSV table when writing each sequence item.