CSV Sampler
Extract a sample of rows from a CSV file
Pull a smaller sample out of a large CSV. Choose how many rows you want and whether to take them randomly, from the top, or from the end, then download a file small enough to work with comfortably.
Sampling is what makes large-file work practical. Testing an import, building a demo, or sharing a file with a colleague rarely needs every row — and a random sample gives a far more honest picture of your data than the first hundred rows, which are usually sorted and unrepresentative.
The header row is always kept, so the sample stays a valid CSV with the same column structure as the source and can be used anywhere the full file would be.
Drop your file here or browse from your device
Accepts CSV, TSV, TXT. Maximum input: 10 MiB. Files above this hard limit are rejected before local processing.
How to Use
- Upload your CSV file or paste CSV data
- Choose the sampling method: random, first rows, or last rows
- Set how many rows the sample should contain
- Review the preview and download the sampled CSV
Features
- Random, first-n, last-n, and every-nth-row sampling
- Seeded random draw, so the same sample can be reproduced
- Configurable sample size
- Header row always preserved in the output
- Preview the sampled rows before downloading
- Keeps the original column structure intact
- Runs entirely in your browser — no upload
Use Cases
- Create a small test file for validating an import
- Build demo or example data from a real dataset
- Share a representative extract without sending the whole file
- Speed up development by working against a smaller file
- Spot-check data quality across a large export
Frequently Asked Questions
Which sampling method should I use?
Random for a representative view of the whole file. First rows when you only need to see the structure. Last rows when the file is chronological and the recent records matter most. Every-nth row gives you an even spread across the file without randomness.
Why is a random sample better than the first hundred rows?
Because files are usually ordered — by date, by ID, by category — so the top rows share characteristics the rest of the file does not. A random sample surfaces the variety and the edge cases that break imports.
Is the header row included?
Always. The sample stays a valid CSV with the same columns as the source.
What if I ask for more rows than the file has?
You get the whole file. The sample size is capped at the number of rows available.
Does sampling change my original file?
No. The file on your computer is untouched; the download is a new, smaller CSV.
What does every-nth-row sampling do?
It takes every nth record — every 10th row, for example — which spreads the sample evenly across the whole file. It is a good choice when the data is ordered and you want coverage from beginning to end rather than a random draw.
Is my data uploaded?
No. Sampling happens in your browser and the contents are not sent to the app server.