Sample files for download testing
Files of exact size for testing download speed, range requests, resuming and integrity.
Testing downloads means answering four questions: does the file arrive complete, does it arrive unmodified, how fast does it arrive, and what happens when the connection drops. Files of exact, published size make each of these measurable.
Use the BIN samples for speed. Their random content cannot be compressed, so no proxy or CDN can make the transfer look faster than it is.
Recommended files
| File | Size | Why this one | Download |
|---|---|---|---|
| 1 MB BIN samplesample-bin-1mb.bin | 1 MB1,048,576 bytes | Quick speed check | Download BIN |
| 10 MB BIN samplesample-bin-10mb.bin | 10 MB10,485,760 bytes | Broadband speed test | Download BIN |
| 10 MB MP4 samplesample-mp4-10mb.mp4 | 10 MB10,485,760 bytes | Range requests and video seeking | Download MP4 |
| File name with spacessample file name with spaces.txt | 34 B34 bytes | File-name handling in download headers | Download TXT |
| 10 MB ZIP samplesample-zip-10mb.zip | 10 MB10,485,760 bytes | Integrity check with a self-verifying format | Download ZIP |
Checklist
Check completeness
Compare the size of the downloaded file with the byte count on the download page.
Check integrity
Compute the SHA-256 of the download and compare it with the published value.
Measure speed properly
Download an incompressible file several times and take the median; discard the first run if a cache is involved.
Test range requests
Request a byte range and expect 206 Partial Content with a Content-Range header.
Test resume
Interrupt a download, then resume it and verify the checksum of the finished file.
Guides
- How to test file downloads
Completeness, integrity, speed, range requests and resume, each with a command you can run.
- How to create test files of any size
Commands for Linux, macOS and Windows that produce a file of an exact byte count, and when to use each.
Related use cases
Frequently asked questions
- Why is my downloaded file smaller than the stated size?
- Either the transfer was cut short, or a tool saved a compressed response without decompressing it. Compare checksums to find out which.
- How do I download only part of a file?
- With curl, use the -r option, for example curl -r 0-1023 to fetch the first 1,024 bytes.