Does incognito mode on Chrome use the cache that was previously stored?

Chrome's incognito mode not only uses a fresh cache and cookie store, but also disposes it off when you close the incognito window.

As an added bonus, no extensions run in incognito windows unless you explicitly allow them from the setting page!

I use the feature myself quite a lot to test and also educate others about it when they cribe that my code is not working, cause 99.99% of the time, their Chrome is infected with some adware plugin / extension which wreaks havoc with a normal website.

No (mostly). When you open your first Incognito window, it’s as if you have a fresh cache. Once you have at least one Incognito window open, it appears that Chrome may use an Incognito-specific cache. I presume this cache is stored in-memory instead of on the disk.

I performed the following testing on Chrome 48:

"Normal" Mode
I loaded a page with a large asset (~18MB) and pulled up the Developer Tools.

When I reloaded the page, the entry for the "large asset" (a video file) showed that the cache was used:

Furthermore, the loading bar both in the Dev Tools as well as on the video player itself progressed to 100% nearly instantaneously. Repeating this test yielded the same results every time.

Incognito Mode
I opened an Incognito Window (none was already open) and repeated the test. This time, I received an HTTP 200 status code again, but the "(from cache)" text was omitted:

Furthermore, the file took 5-10 seconds to download, and the loading bar in the Dev Tools and on the video player showed that it took 5-10 seconds to progress to 100%. I should also point out that subsequent reloads/tests while in Incognito Mode yielded the same result.

What does this mean? In Chrome, when you open your first Incognito Mode window, the cache is not used. For future requests, it appears that the cache may be used (Chrome Canary 54). To ensure the cache isn’t being used, close your Incognito windows and open a new one.