Heart rate
Also calledHR · ventricular rate · heart rate (bpm)
Definition
The number of ventricular depolarizations (QRS complexes) per minute, expressed in beats per minute (bpm). When the rhythm is regular and the paper runs at the standard 25 mm/s, it can be estimated as 300 divided by the number of large (5 mm, 0.2 s) boxes between consecutive R waves, or 1500 divided by the number of small (1 mm, 0.04 s) boxes. When the rhythm is irregular, the complexes are counted over a longer strip instead: for example, the QRS complexes in a 6 second strip multiplied by 10, or the R-R intervals in a 10 second strip multiplied by 6.
Clinical noteThe 300 and 1500 shortcuts assume the standard 25 mm/s paper speed; at 50 mm/s they become 600 and 3000.
Sources
- Kligfield P, Gettes LS, Bailey JJ, et al. Recommendations for the standardization and interpretation of the electrocardiogram: part I: the electrocardiogram and its technology. Circulation. 2007;115(10):1306-1324. doi.org/10.1161/CIRCULATIONAHA.106.180200
- Samesima N, God EG, Kruse JCL, et al. Brazilian Society of Cardiology guidelines on the analysis and issuance of electrocardiographic reports - 2022. Arq Bras Cardiol. 2022;119(4):638-680. doi.org/10.36660/abc.20220623
- Meek S, Morris F. ABC of clinical electrocardiography. Introduction. I: Leads, rate, rhythm, and cardiac axis. BMJ. 2002;324(7334):415-418. doi.org/10.1136/bmj.324.7334.415
Last reviewed 2 October 2026. Every definition in the EKG Dictionary cites the guideline, consensus statement or original paper it comes from.