Joshua's Docs - Sniffing Image CDNs and Transformation Services

Common URL Patterns

I've been around image CDNs and transformation APIs enough to recognize when an image URL is pointing to one. However, determining which one in particular can be a little bit of a chore, so I've come up with a handy table that makes it easier.

This is a wide table - you can horizontally scroll

Service 👉

Params 👇
Cloudinary imgproxy Cloudflare (see also worker docs) ImageOptim Statically Netlify (Large Media Transformation) Glide
Key-Val Approach /{key}_{val},... /{key}:{val}/... /{key}={val},.../

Docs specify comma-separated kv-pairs, but I've also seen standard & used
/{key}={val},.../ /{key}={val},.../ ?{key}={val}&... ?{key}={val}&...
Param: Quality q_{percent}
Example: q_70
quality:{percent} quality={percent} or q={percent} quality={preset}
Example: quality=low
q={percentage} NA q={percentage}


I might add to this section eventually, but for right now I'm going to leave this blank with the reasoning that relying on response headers to determine how an image was processed is less reliable (in general) than looking at the syntax of the request URL.

All sorts of setups can interfere with getting the original headers back from the transformation layer, and some services don't return unique headers that you can depend on staying immutable over time anyways.

Markdown Source Last Updated:
Sun Apr 04 2021 20:00:05 GMT+0000 (Coordinated Universal Time)
Markdown Source Created:
Thu Mar 25 2021 23:02:16 GMT+0000 (Coordinated Universal Time)
© 2021 Joshua Tzucker, Built with Gatsby