Cartridge Battery Life Estimator
Estimate how much life is left in your cartridge's save battery. Know before your Pokémon data disappears.
Quick-fill famous saves
How to Replace a Cartridge Battery
- 1Obtain the correct replacement battery (usually CR2032). Check the cartridge label or open it to confirm.
- 2Open the cartridge using a security bit (3.8 mm gamebit for Nintendo, regular Torx T8 for some). Do NOT use a standard Phillips screwdriver.
- 3Tabbed battery: The battery is held by metal tabs soldered to the board. Slide the old battery out and snap a new one in. No soldering needed.
- 4Soldered battery: The battery leads are soldered directly to the PCB. Use a soldering iron to carefully desolder the old battery, then solder in a new one (with tabs, to avoid heating the new cell directly). This takes ~5 minutes with basic soldering skills.
- 5Important: Before removing the old battery, load your save and take a photo/note of important data, as the save WILL be erased when power is interrupted.
- 6Reassemble the cartridge, test the save function, and you are done.
About Cartridge Save Batteries
Many cartridges from the NES through the N64 era used small lithium coin-cell batteries (most commonly CR2032) to power a small amount of SRAM that retained save data when the console was off. These batteries typically last 10–20 years from manufacture date, depending on temperature, storage conditions, and how often the cartridge was used.
A dead battery does not damage the cartridge — you simply lose the ability to save new games and any previously saved data is gone. The game itself still plays normally from any save slot, but saves cannot be written or retained.
Replacement batteries cost under $1 each and the procedure is straightforward for most cartridges, even for beginners with basic tools.