A 1 MB TXT test file

About this file

A 1 MB test file in TXT format, sized to exactly 1,048,576 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

1 MB is exactly the nginx client_max_body_size default (1m). Behind a reverse proxy where nobody set that directive, anything larger never reaches your application — nginx answers 413 Request Entity Too Large itself.

That makes it the ideal size for reproducing the classic incident where the app limit was raised to 10 MB yet uploads still fail at 1 MB. If the 413 never appears in your application log, the cause is almost always the proxy layer in front of it.

Getting a feel for this size

On a 10 Mbps link the transfer takes roughly 839 ms, and about 84 ms at 100 Mbps. Base64-encoded it grows to roughly 1,365 KB.

At roughly 120 bytes per log line, this size holds about 8,738 lines — a reasonable basis for estimating how long log aggregation or a full-text scan will take. Line length varies, so treat it as an approximation.

What to check for this format

Plain text is the simplest format, yet two variables alone — character encoding and newline convention — account for a large share of real defects. It carries no signature, so its format cannot be confirmed from the bytes.

• Whether you read line by line — slurping a log-sized text file whole puts heavy pressure on memory
• Whether the presence or absence of a BOM changes your processing
• Whether the final line is still captured when the file does not end with a newline