legal
Terms of Service.
last updated · 14 july 2026
What RhythmBio is
RhythmBio charts four biorhythm cycles computed from your date of birth and turns them into daily scores, forecasts, briefings, journaling, and family tracking. By creating an account you agree to these terms.
Not medical advice
RhythmBio is a self-reflection tool, not a medical device or a source of medical, psychological, or professional advice. Biorhythm theory is a contested framework: the fixed cycle periods have not been validated in controlled scientific studies. Never use the app to make decisions about your health, medication, treatment, or safety, and never delay seeking professional advice because of something the app told you. If a briefing and your doctor disagree, listen to your doctor.
Your account
You must be 16 or older. Keep your credentials to yourself and give us accurate information. The app literally runs on your date of birth. You're responsible for activity on your account. If you add family members, make sure you're entitled to share their details with us.
Subscriptions & billing
The free tier is free forever for individual use. Pro and Family are paid subscriptions billed in GBP through Stripe, renewing automatically each month or year until cancelled. You can cancel any time from Settings; access continues to the end of the period you've paid for. Prices may change with notice before your next renewal. Nothing in these terms affects your statutory consumer rights.
Acceptable use
Don't abuse the service: no attempting to break, probe, or overload it, no scraping other people's data, no reselling access, and no using the AI briefings to generate content that's unlawful or harmful. We can suspend accounts that do.
Your content, our service
Your journal entries and data remain yours; you give us the licence needed to store and process them to run the service. The RhythmBio name, design, and software remain ours. We work hard to keep the service up, but it's provided “as is”. To the maximum extent the law allows, we're not liable for indirect losses, and our total liability is capped at the amount you paid us in the twelve months before a claim.
Ending things
You can delete your account from Settings whenever you like. It takes your data with it. We may terminate accounts that breach these terms, and we'll refund any unused subscription period if the termination wasn't your fault.
Changes & contact
If we change these terms materially we'll update the date above and notify subscribers by email before the change takes effect. Questions: hi@rhythmbio.app.