Privacy Notice
Last updated: July 25, 2026
The short version
- We never sell your personal data.
- We never use your videos to train AI models.
- Nothing is shared publicly unless you share a run link or image yourself.
- Deleting a run removes its video, annotated video, charts, and metrics from our storage.
What we collect, and why
| What | Why |
|---|---|
| Your videos (MP4/MOV) and the annotated videos and charts we generate | They're the input and output of the analysis — we can't measure your form without them |
| Your height | Converts on-screen distances to real-world ones (stride length, bounce) |
| Derived metrics: cadence, joint angles, stride and gait data | The results we show you, and your progress over time |
| Account info: email, name (via Clerk, our sign-in provider) | Sign-in and account management |
| Payment and subscription status (via Stripe) | Billing — your card details go to Stripe and never touch our servers |
| Usage analytics (via PostHog): pages viewed, features used | To see what works and fix what doesn't |
| Emails you send us, and referral codes | Support, and crediting referrals |
That's the whole list — no location tracking, no contacts, no background collection.
A note on video and body data
Analyzing your running form means processing footage of your body and computing measurements from it (like joint angles and stride length). We treat this as the most sensitive data we hold: we ask for your explicit consent before your first upload, we record when you gave it and to which version of this notice, and we won't accept uploads without it. If this notice materially changes, we'll ask you to review and accept the new version before your next upload.
How your video flows
You upload a video over an encrypted connection. Our servers analyze it — a computer-vision model tracks your joints frame by frame and computes your metrics. The video, its annotated version, and your results are stored in access-controlled cloud storage and served only through short-lived signed links. Processing happens on our servers, not on your device — we'd rather tell you that plainly than imply otherwise.
Who processes data on our behalf
| Service | Purpose |
|---|---|
| Clerk | Sign-in and account management |
| Vercel | Website hosting |
| Render | API hosting and video processing |
| Cloudflare R2 | Video and image storage |
| Stripe | Payments |
| PostHog | Product analytics |
These providers process data only to run Runlens. We don't sell your personal data to anyone, and we may disclose data if the law requires it.
Sharing and public links
Every run has a results page reachable by a long, unguessable link. It's not listed anywhere — but anyone you give the link to can see that run's annotated video, metrics, and charts. They cannot see your name, email, raw (unannotated) upload, or other runs. Deleting the run disables the link.
How long we keep your data
Your videos and results are kept until you delete them — there's no automatic expiry, so your run history is there when you come back. Deleting a run removes its video, annotated video, charts, and metrics from our storage. Consent records are kept as an audit log. Billing records are retained as required for accounting.
Your controls
- Delete any run — from your Runs page, anytime.
- Delete everything — email hi@runlens.io from your account's email address and we'll delete your account and all associated runs, videos, and results within 30 days.
- Get a copy of your data — email us and we'll send you what we hold about you.
Security
Data moves over encrypted connections (TLS). Videos and images live in access-controlled storage and are served via signed URLs that expire within an hour. Payments are handled end-to-end by Stripe, a PCI-DSS-compliant processor — card numbers never touch our servers.
Age
Runlens is for adults: you must be at least 18 to create an account. We don't knowingly collect data from anyone younger; if we learn we have, we'll delete it.
Changes to this notice
We'll post updates here with a new "last updated" date. For material changes, we'll ask you to review and re-accept before your next upload.