Find a bike lock that fits your daily parking spot
Start with the rack you use most. The shape and usable reach of a lock matter as much as how easily you can carry it on a ride.
Folding lock, U-lock or chain?
A folding lock packs into a compact mount. A U-lock has a fixed opening; a chain can wrap around a wider anchor. Compare the usable dimensions of the exact model.
Will it fit my frame and rack?
Measure the route from the frame around the fixed rack. Check mount clearance, carrying weight and the security certification for that specific model.