Why is the delimiter wrong?

Detection compares how consistently each candidate splits the first lines. If a file is unusual, choose the delimiter manually.

Can it open very large files?

Files up to about 20 MB are comfortable. The whole file is held in memory on your device, so much larger files depend on how much memory you have.

Does it change my file?

No. It only displays it — there is nothing to save and the original is untouched.

CSV Viewer

Open a CSV as a sortable, filterable table and see which rows are malformed.

Processing: This tool runs entirely in your browser. Your input and any file you open stay on your device — nothing is uploaded to a server.

How to use the csv viewer

Open a CSV file or paste the text.
Sort by clicking a column heading, or type in the filter box.
Check the malformed-row warning if one appears.

About this tool

Opening a CSV in a spreadsheet is a commitment: it may reformat dates, strip leading zeros from identifiers and convert long numbers to scientific notation before you have even looked at the data. This just shows you the file — every value exactly as written.

Columns sort numerically when both values are numbers and alphabetically otherwise, the filter matches any cell in a row, and rows are paged so a large file stays responsive. Rows whose field count differs from the header are counted and the first is pointed out, which is the fastest way to find an unescaped quote.

The file is read on your device. For a customer export or anything with personal data in it, that is the difference between inspecting a file and disclosing it.

Common uses

Checking an export before importing it somewhere.
Finding the row that breaks a bulk upload.
Reading a CSV without letting a spreadsheet reformat it.

Frequently asked questions

Why is the delimiter wrong?: Detection compares how consistently each candidate splits the first lines. If a file is unusual, choose the delimiter manually.
Can it open very large files?: Files up to about 20 MB are comfortable. The whole file is held in memory on your device, so much larger files depend on how much memory you have.
Does it change my file?: No. It only displays it — there is nothing to save and the original is untouched.

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