How can I force Google Chrome to cache images?

There's a website I use every day, and there are lots of large images on it (uploaded by my designers).

Every time I go to a page, the images get downloaded again, and it takes forever. How can I force Chrome to cache these images?

Once uploaded, they never change. More images are uploaded each day, but when I go to a page, ALL of the images are downloaded-- even ones Chrome has downloaded before.

I suspect I may need a Chrome extension.

It might be a bit overkill, but you could run a caching proxy like squid on your client computer and redirect all your browsers (maybe all 1 of them) to use the local proxy. Then in the proxy you can more easily force caching of the content you want.

You'll have to use SSL-interception w/the proxy to see individual items, since google promotes SSL-obfuscation everywhere, you won't be able to see anything unless your proxy acts as a MITM.

Since I added SSL interception to my home proxy my caching rate has gone up to as high as 30-45% of requests, though more commonly its down around 10-15% of requests 5-10% of byte-volume.

I put in special filters to force image caching on some sites to improve performance. My housemate notices it when browsing youtube and how much faster browsing is now because the thumbs are cached locally.

It might very well be overkill for your use case, but it does give you a lot of access to things that are normally closed-off to users w/https-everywhere.