Built for 3 AM.
Wake-window predictions from your baby's actual patterns, with a Calm Mode for the days when tracking is making it worse. Free on one device, sync for $5/mo.
What Rhythm does
Sleep and wake predictions
From your baby's actual patterns, not a model trained on someone else's. Rhythm reads your baby's sleep history, finds the days that looked like today, and shows you the wake window that usually follows. Every number shows its work: how many days it learned from, which method it used, what it doesn't know yet. If it looks wrong, you override it - your call always wins. And because it all runs on your phone, the app works offline by default: traveling, basement, hospital wifi that pretends to exist. Everything syncs when you're back.
Coming from Huckleberry? See how Rhythm compares →
Calm Mode
Sometimes tracking makes it worse. Calm Mode softens the timers, hides the warnings, and tucks the predictions away. Everything is still saved, it's just no longer grading you. And if a tile is the thing stressing you out, you can hide it for good in customization. More on Calm Mode →
Partner Sync
Your partner opens their phone and the last feed is already there - no "did you log it?" texts, no comparing notes at handoff. Invite them with a QR code and every device stays current. Sync is the one thing behind the $5/mo, and it's per household, not per person, so the whole family is one price. On the free tier everything still works; it just stays on the one device you set it up on.
Midnight Mode
Turns your screen true black with red-shifted light so you can log a dream feed without blinding yourself. All icons and colors shift, tap targets and text grow, it can be scheduled, or automatically turn on when low light is detected.
There's more.
Milk Stash
Pumped bags tracked by location and expiration, with a days-of-supply estimate from what your baby actually eats. See the stash tracker →Custom everything
Build your own event types and status tiles, then rearrange the dashboard to match your family. Build your own →Eleven themes
Four primary, seven programmer palettes, or build your own - each with a light and dark variant. Browse the themes →Honest pricing
Free
$0 one device, forever
- The full app: predictions, custom events, themes, Calm Mode, Midnight Mode
- No ads, no tracking, no data selling
- Export your data anytime (JSON)
- Stays on the one device you set it up on
Household sync
$5/mo or $45/yr - per household, not per person
- Everything in Free, on every device
- Invite your partner, a grandparent, or a nanny by QR code - all one price
- Cloud backup, encrypted in transit, encrypted backups
- 14-day free trial, cancel anytime - your local data stays put
Questions
How much does Rhythm cost?
Free forever on one device, or $5/month ($45/year) for sync, partner access, and cloud backup - cancel anytime.
How does partner sync work?
Add your partner or a grandparent to your household and their phone shows the same feed within seconds, with one price covering everyone and no per-seat fees.
Where is my baby's data stored?
On your device first; if you sync, an encrypted copy also lives on my servers so your other devices can read it - see Privacy for the full breakdown.
Does Rhythm work offline?
Yes - everything you log saves to your phone first and syncs to your other devices once you're back online.
Do I need to install an app from the App Store?
No - open app.rhythm.baby in any browser, then add it to your home screen (on iPhone tap Share then "Add to Home Screen"; on Android use the page menu).
Can I export my data?
Anytime and free - export to JSON for your own backups or to leave, because your data is yours.
I'm a security engineer, and a dad, who built Rhythm by the glow of the baby monitor for my own son. My wife and I used it for months before I felt good about handing it to anyone else. If something's broken or a feature doesn't make sense, email me: support@rhythm.baby.