A 100 KB JPG test file

About this file

A 100 KB test file in JPG format, sized to exactly 102,400 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

100 KB sits at the boundary between "trivially small" and "realistic payload". It is close to the total transfer weight of a single lean web page and is a common target size for performance-conscious images.

It clears the sub-1 MB caps many applications impose, but it is still small enough that a naive load-everything-into-memory implementation works fine — so it is not the right size for proving that streaming is necessary. Pair it with 10 MB or larger to see the difference.

Getting a feel for this size

On a 10 Mbps link the transfer takes roughly 82 ms, and about 8 ms at 100 Mbps. Base64-encoded it grows to roughly 133 KB.

Estimating a photographic JPG at roughly 0.2 bytes per pixel, this size works out to around 512,000 pixels — about 826 × 620 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

JPEG is lossy and has no transparency. Its signature begins with FF D8 FF. The single most common defect in real implementations is ignoring the EXIF Orientation tag, which makes rotated photos appear sideways in the browser.

• Whether you read EXIF Orientation and auto-rotate, or deliberately strip it
• Whether privacy-sensitive data such as GPS coordinates remains — stripping is mandatory for user-submitted images
• Whether both progressive and baseline JPEG decode correctly — older decoders sometimes fail on progressive