A 50 MB GIF test file

About this file

A 50 MB test file in GIF format, sized to exactly 52,428,800 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

50 MB is the point where GitHub starts warning you on push (it hard-rejects above 100 MB). In practice it is the decision line for whether a binary belongs in Git directly or should move to Git LFS.

At this scale, an implementation that buffers the whole request in memory burns 50 MB or more per worker process — ten concurrent uploads means 500 MB. It is a good size for verifying that streaming or spill-to-temp-file actually works.

Getting a feel for this size

On a 10 Mbps link the transfer takes roughly 41.9 seconds, and about 4.2 seconds at 100 Mbps. Base64-encoded it grows to roughly 68,267 KB.

Estimating a photographic GIF at roughly 0.5 bytes per pixel, this size works out to around 104,857,600 pixels — about 11,824 × 8,868 px at a 4:3 aspect ratio. Compression varies enormously with image content, so treat this purely as an order-of-magnitude figure.

What to check for this format

GIF begins with the ASCII signature GIF87a or GIF89a and uses a palette of up to 256 colours. Because it can hold multiple animation frames, code written for single-frame images either grabs only the first frame or, worse, expands every frame and consumes far more memory than expected.

• Whether resizing an animated GIF preserves the animation or flattens it to a still
• Whether thumbnail generation correctly extracts the first frame
• Whether you cap memory when expanding all frames — usage grows with frame count multiplied by resolution