Column Type Inferencer
Paste tabular text to estimate whether each column looks like text, integer, decimal, boolean, date, or null.
COLUMN TYPE INFERENCER
Estimate likely types from bounded CSV or TSV samples.
Local heuristics only; this is not schema validation or a guarantee for future rows.
| Column | Likely type | Samples | Confidence |
|---|
A QUICK WALKTHROUGH
How to use this tool
- Paste CSV or TSV data with a header row.
- Choose the delimiter and infer types from up to 1,000 rows.
- Review sample counts and confidence before defining a real schema.
Bounded local inference
The browser samples up to 1,000 data rows and 100 columns. Empty cells count as null observations; mixed values lower confidence.
Heuristics, not validation
Integer, decimal, boolean, and ISO-like date rules are intentionally conservative. Locale-specific dates, IDs with leading zeroes, and domain-specific values may be classified as text.
GOOD TO KNOW
Common questions
Does this create a schema?
No. It reports likely types for review and does not guarantee future rows.
Are files uploaded?
No. Pasted data stays in this browser tab.
Can it infer every date format?
No. It recognizes a narrow ISO-like date pattern only.