You will find many websites offering "free BIOS downloads." However, BIOS code is copyrighted intellectual property owned by the original console manufacturers (Sony, Sega, Atari, etc.). Distributing these files without permission is software piracy.
Legitimate ways to obtain BIOS files:
No legitimate emulator developer, including the Lemuroid team, provides or hosts BIOS files. Any website claiming "Lemuroid BIOS pack free download" is distributing copyrighted material without authorization. lemuroid bios files free
The short answer is: It depends on the console.
Lemuroid includes open-source emulation cores that can run many games without BIOS files. However, for accuracy and copy protection, some cores require official BIOS dumps. You will find many websites offering "free BIOS downloads
If you own a PlayStation console (PS1, PS2, or PS3), you can dump your own BIOS. This requires specific hardware (like a USB BIOS dumper or a compatible PS2 memory card adapter) and software. It is time-consuming, technical, but completely legal for personal backup purposes under most copyright laws (DMCA exemptions for emulation).
Never download a file named bios_installer.exe. BIOS files are raw binary data—usually .bin or .rom files. If a site tries to give you an executable, run away. No legitimate emulator developer
Paste your .bin BIOS files directly into the system folder. Do not put them in a subfolder.
Correct path example:
/storage/emulated/0/Android/com.swordfish.lemuroid/files/system/scph5501.bin