Browser.cache.memory.capacity Apr 2026

The value of browser.cache.memory.capacity is measured in kilobytes (KB). When Firefox starts, it allocates a portion of memory based on this value. As you browse the web, Firefox stores cache entries in this allocated memory. When the cache grows, Firefox uses a least-recently-used (LRU) algorithm to evict older cache entries to make room for new ones.

A Firefox configuration parameter!

The default value of browser.cache.memory.capacity varies depending on the system and Firefox version. On a typical system, the default value might be around 50-100 MB (50,000-100,000 KB). Browser.cache.memory.capacity

Here's some information on the browser.cache.memory.capacity parameter: The value of browser