The dumbbell bicep curl is the most popular isolation exercise for building the biceps. Because each arm works independently, it evens out side-to-side strength differences and lets you train through a full range of motion.
Muscles worked
Primary: Biceps brachii.
Secondary: Brachialis, Forearm flexors.
Equipment: Dumbbells · Difficulty: Beginner.
How to do the dumbbell bicep curl
- Stand tall holding a dumbbell in each hand, arms hanging at your sides, palms facing forward.
- Keep your elbows pinned to your sides and your upper arms still.
- Curl the dumbbells up by flexing at the elbow until they reach shoulder height.
- Squeeze the biceps hard at the top for a moment.
- Lower under control over 2–3 seconds back to the start. That is one rep.
Common mistakes to avoid
- Swinging the torso to heave the weight up — this shifts load off the biceps. Use a weight you can lift strictly.
- Letting the elbows drift forward, turning it into a front raise.
- Dropping the weight quickly instead of controlling the lowering (eccentric) phase, where much of the growth happens.
Track it automatically with Spotwell
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