OpenCap
OpenCap estimates 3D human movement kinematics and forces from smartphone video for biomechanical analysis.
What OpenCap is
OpenCap estimates 3D human movement kinematics and forces from smartphone video for biomechanical analysis. It provides joint angles, moments, and muscle forces through musculoskeletal dynamics, with example analyses including walking, sit-to-stand, squats, drop jumps, treadmill running, and jumping. Recording uses iOS devices, while users review and download data through a web app; videos are processed on cloud servers. Capture can use multiple cameras or a beta monocular mode with one iPhone, which requires no calibration. Python utilities support further analysis, including kinetics estimation, and exports include JSON, TRC, and MOT. The maker says OpenCap has been validated against marker-based systems and that data is encrypted in transit and at rest on HIPAA-compatible infrastructure. The service is free for academic or nonprofit non-commercial research and educational use. Commercial entities, including those conducting research, are prohibited from using it and are directed to contact the authors. The development team can view submitted data, including videos, and may use it for algorithm development; investigators must obtain participant consent.
Good
- Estimates joint angles, moments, and muscle forces.
- Offers multi-camera and beta one-iPhone capture.
- Includes Python utilities and JSON, TRC, and MOT exports.
- Free for academic or nonprofit non-commercial research and education.
- Maker reports encryption and HIPAA-compatible infrastructure.
Watch out
- Commercial entities are prohibited from using the service.
- Development team can view submitted data, including videos.
- Recording requires iOS devices; Android is not supported.
- Monocular capture is in beta.
Who it suits
OpenCap suits academic or nonprofit teams conducting non-commercial movement research or education with iOS devices. Participants and investigators should consider the data access and consent terms before submitting videos.
Verdict
OpenCap provides a video-based workflow for biomechanical analysis with multiple capture options and downloadable data. Its non-commercial use restriction and submitted-video access terms deserve careful review.
Plans and prices
From OpenCap's own pricing page, checked 5 Oct 2026.
| Plan | Price | What it gives you |
|---|---|---|
| OpenCap | Free | Free for academic or nonprofit non-commercial research or educational use · commercial entities must contact the authors |
The facts
Each one read from OpenCap's own pages, with the date it was checked.
What it does
- Analysis utilities
- OpenCap provides Python utilities for further analysis, including estimating kinetics.checked 5 Oct 2026
- Capture modes
- It offers multi-camera capture and a beta monocular setup that records with one iPhone.checked 5 Oct 2026
- Commercial use
- The service terms prohibit use by commercial entities, including for research, and direct interested entities to contact the authors.checked 5 Oct 2026
- Data access
- OpenCap's terms say the development team can view submitted data, including videos, and may use it for algorithm development.checked 5 Oct 2026
- Data sharing
- Investigators must obtain participant consent, and participants can choose among several levels of public data sharing, including no public sharing.checked 5 Oct 2026
- Monocular requirements
- The monocular instructions require one iPhone for recording and say no calibration step is needed.checked 5 Oct 2026
- Outputs
- The platform provides joint angles, moments, and muscle forces through musculoskeletal dynamics.checked 5 Oct 2026
- Purpose
- OpenCap estimates 3D human movement kinematics and forces from smartphone video for biomechanical analysis.checked 5 Oct 2026
- Security
- The maker says data is encrypted in transit and at rest and that its infrastructure is HIPAA-compatible.checked 5 Oct 2026
- Support
- The contact page directs technical questions to the multi-camera or monocular forums before emailing and says Android is not supported.checked 5 Oct 2026
- Use cases
- The site lists walking, sit-to-stand, squats, drop jumps, treadmill running, and jumping as example movement analyses.checked 5 Oct 2026
- Validation
- The maker says OpenCap has been validated against marker-based systems.checked 5 Oct 2026
- Workflow
- Users record with iOS devices, review and download data through a web app, and process videos on cloud servers.checked 5 Oct 2026
Where it runs
- Device requirements
- The multi-camera instructions require at least two iOS devices and say iPhones, iPads, and iPods released in 2018 or later are supported.checked 5 Oct 2026
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