Reviewed 2026-08-28

Validate CSV Before Importing It

Check dialect, headers, row shape, required values, and spreadsheet hazards.

id,name,amount
1,Ada,12.50
2,Grace,

2 rows; amount missing on row 2

Reproducible method

1. Preserve the original and create the smallest representative sample.
2. Run a strict parse or validation before transformation.
3. Record options, compare counts and structure, then test in the receiving system.

Common error

A rectangular table can still contain invalid domain values.

Reduce a failure while retaining the problematic structure; this separates malformed input from unsupported behavior.

Technical limitation

Generic validation cannot infer every business rule.

A successful preview does not remove format ambiguity or downstream requirements.

Security and privacy

Quarantine rejected rows and flag formula prefixes.

Local processing reduces transfer risk but cannot protect a compromised browser, unsafe extensions, clipboard history, or later misuse.

Verification checklist

• Check field, record, page, or byte counts.
• Review edge cases and error output.
• Retain the original until acceptance.
• Document assumptions for automation.

Open the related tool