A 10 KB CSV test file

About this file

A 10 KB test file in CSV format, sized to exactly 10,240 bytes. Free to download with no signup, for verifying upload limits and file-handling behaviour.

The MD5, SHA-1 and SHA-256 values listed above are the real digests of this file. Recomputing them after download confirms the transfer was not corrupted, and they double as known-good expected values when testing a hashing library.

What this size means in practice

10 KB sits below virtually every upload limit, which makes it the baseline "happy path" case. Confirm this file goes through first, then move up in size to probe where your limits actually bite.

It also fits inside the AWS Lambda asynchronous invocation payload cap (256 KB) and typical API JSON body limits. The size is convenient for CI fixtures and unit-test data you commit to a repository.

Getting a feel for this size

On a 10 Mbps link the transfer takes roughly 8 ms, and about 1 ms at 100 Mbps. Base64-encoded it grows to roughly 13 KB.

For a typical business CSV of about ten columns and roughly 100 bytes per row, this size corresponds to about 102 rows — a useful gauge for whether a spreadsheet can open it or a bulk database import finishes in time. It is a rough estimate; actual counts vary with content and column count.

What to check for this format

CSV is plain text and has no magic bytes of its own. You therefore cannot prove a file is CSV by inspecting a signature; validation has to focus instead on character encoding, delimiters, and quoting rules.

• Whether you process row by row instead of loading every line into memory — the classic cause of out-of-memory failures on large CSVs
• Whether quoted values containing embedded newlines or commas are parsed correctly
• Whether encoding detection is correct — CSVs containing Japanese are a frequent source of mojibake