Around the Supercross BMX Shop we tend to use Park and Shimano tools. Not because we are sponsored by them or endorsed or have an affiliate program, just because they work.
The Shimano "Team" Chain Tool easily breaks chains to your desired length.
Extra Durable Heat Treated Steel
Ergonomic Grip
Longer Twistgrip for Increased Leverage
8, 9, 10, and 12 Speed Compatible