CSV Column Type Validator
Declare each CSV column's expected type, then find the exact rows and cells that do not match. Supports int, float, bool, date, enum values, headers or column indexes, delimiter auto-detect, and JSON output.
About this tool
CSV Column Type Validator checks selected CSV columns against a small declared schema and reports every cell that does not match. It is useful before importing spreadsheets, partner exports, or analytics feeds into a stricter system.
Declare types with a comma- or newline-separated list such as:
age:int, score:float, active:bool, joined:date, plan:enum(free|pro)
Then paste CSV data. With a header row enabled, declarations use header names. With First row is a header disabled, declarations use 1-based column indexes such as 2:int, 3:enum(free|pro).
Worked example
Input data:
name,age,score,active,joined,plan
Ada,34,9.5,true,2021-06-01,pro
Bo,twelve,8,yes,2021/06/02,gold
Types:
age:int, score:float, active:bool, joined:date, plan:enum(free|pro)
The report marks the CSV invalid and lists three offending cells: row 2 age is not an integer, row 2 joined is not an ISO date, and row 2 plan is outside the allowed enum values.
Supported checks
- int — signed whole numbers like
42or-7. - float — decimal or scientific notation like
3.14,.5,2., or1e6. - bool —
true/false,1/0,yes/no,t/f,y/n(case-insensitive). - date — controlled by Date format: ISO
YYYY-MM-DD, USMM/DD/YYYY, EUDD/MM/YYYY, or any of those. - enum(a|b|c) — exact allowed values; enum matching is case-sensitive after trimming whitespace.
Limits and edge cases
The parser handles quoted fields, doubled quotes, delimiters inside quotes, quoted newlines, and blank physical lines. It auto-detects comma, tab, semicolon, and pipe delimiters from the first non-blank line. It does not perform regex validation, min/max numeric ranges, email/phone/postal checks, type coercion, or automatic fixing; it is a report-only type checker.
CLI example:
gizza tool csv-column-type-validator data="name,age
Ada,34
Bo,x" types="age:int" header=true delimiter=comma date_format=iso empty_ok=true max_issues=50 format=text
FAQ
How do I validate a CSV without headers?
Turn off First row is a header, then refer to columns by 1-based index in the type declaration. For example, 2:int, 3:enum(free|pro) validates the second column as an integer and the third column against the two enum values.
What happens when I declare a column that is not in the CSV?
The result is invalid even if no cell-level type errors are found. Unknown declared columns usually mean a misspelled header, a delimiter mismatch, or a headerless file being checked with header mode still enabled.
Are empty cells valid?
By default, yes: blank checked cells are allowed. Disable Allow blank cells to make every checked cell required; blank values will then be reported as empty cell (required).
Can this validate emails, phone numbers, regexes, or numeric ranges?
No. This tool focuses on coarse column types: integer, float, boolean, date, and enum. Use dedicated validators for business-specific formats, or pre-clean the CSV before running this type check.
Developer & Automation Access
Run it from the terminal
Same engine as this page, headless — via the gizza CLI:
gizza tool csv-column-type-validator "name,age,score,active,joined,plan
Ada,34,9.5,true,2021-06-01,pro
Bo,twelve,8,yes,2021/06/02,gold" 'types=age:int, score:float, active:bool, joined:date, plan:enum(free|pro)'New to the CLI? Get gizza →
Open it by URL
Pre-fill and auto-run this tool with query parameters — the names match the API/CLI:
https://gizza.ai/tools/csv-column-type-validator/?data=name%2Cage%2Cscore%2Cactive%2Cjoined%2Cplan%0AAda%2C34%2C9.5%2Ctrue%2C2021-06-01%2Cpro%0ABo%2Ctwelve%2C8%2Cyes%2C2021%2F06%2F02%2Cgold&types=age%3Aint%2C%20score%3Afloat%2C%20active%3Abool%2C%20joined%3Adate%2C%20plan%3Aenum%28free%7Cpro%29&header=true&delimiter=auto&date_format=iso&empty_ok=true&max_issues=50&format=textMachine-readable descriptor: tool.json — title + parameters JSON Schema for agents.