Stock ROM — also called stock firmware or factory firmware — is the original operating system software that a phone or tablet comes with when it leaves the factory. It is the official software released by the manufacturer for a specific model, and it is different from custom ROMs (third-party Android builds) because it contains only the manufacturer's own apps, settings, and system configuration. When you flash a stock ROM, you are putting the phone back to exactly the state it was in on day one.
The most common reason to download stock firmware is to recover a bricked or broken device. When a phone gets stuck in a boot loop, fails to start, or shows a blank screen after a bad update, flashing the official firmware is the most reliable fix. It is also used to remove custom ROMs — for example, if you want to return a rooted Samsung device back to a clean, official Samsung state before selling it or sending it in for warranty service. You can find the right Samsung firmware at our Samsung Stock ROM page, or Xiaomi firmware at our Xiaomi Stock ROM page.
To flash stock firmware, you need three things: the correct firmware file for your exact model number, the matching flashing tool for your device's chipset or brand, and the correct USB driver installed on your Windows PC. Using the wrong firmware file — even for a slightly different model — can cause additional problems, so always confirm the model number before downloading. Each brand page on this site lists the models it supports.