Dose log
Your next dose is front and centre with a countdown. One tap logs dose, time, site and draw together. Undo in a beat, or backfill a dose you logged late.
FreeProtocol tracker · peptides & GLP-1s
Your protocol, tracked like data.
STACK is the protocol tracker for peptides and GLP-1s. One-tap dose log, an estimated-level curve built from published half-lives, your titration schedule, reminders, injection-site rotation, vial inventory, weight and side effects — and a PDF report for your clinician. Free to track.
Works in your phone's browser today. iPhone and Android apps are coming.
What it tracks
Everything a protocol is made of, in one log.
Nine things, recorded together and shown back clearly. Tracking is free. Pro adds the analysis layer.
Estimated-level curve
A one-compartment model of the doses you actually logged, using the published half-life you set. Drag to scrub any hour. Always labelled an estimate — never a blood level.
Free 7-day · Pro full rangeTitration schedule
Enter the plan your prescriber gave you. STACK schedules every dose from it and shows where you are in the plan. It never proposes a step.
FreeReminders
A local notification before each scheduled dose, with Log and Snooze on the notification itself. Nothing leaves your device.
Free · Pro per-compound smart timingInjection-site rotation
A front-body map. Sites used in the last 14 days are greyed, the next rotation site is highlighted, and you can override with a tap.
FreeVial inventory
Track what is left in the vial in doses, not guesses. Reconstitution writes the concentration onto the vial, so every log carries its draw.
FreeWeight and side effects
Weight, manual or synced from Apple Health / Health Connect, and side-effect notes sit on one timeline with your doses and photos.
FreePDF report
A clean 90-day report — doses, adherence, weight trend, side effects and the curve — to hand to your clinician.
ProOptional account and sync
Sign in with an emailed code and the same STACK appears on every device you own. No account, and it stays exactly the local-first app it always was.
FreeThree free tools
The app's math, open to anyone.
The same functions that run inside STACK, on the web, no sign-in. Each one shows its working and says plainly what it does not do.
01 · Peptide calculator
Reconstitution and dose to units.
Enter the vial, the diluent and the dose you were given. Get the concentration, the draw volume and the units on a U-100 syringe, with a barrel gauge for 0.3, 0.5 and 1 mL. A unit converter — it never suggests a dose.
Open the calculator02 · Level simulator
See what a half-life does over weeks.
Pick a reference compound with its published half-life, or type your own, choose a schedule and a duration, and watch the estimated level build toward steady state. Scrub any day. Shown as a percentage of the steady-state peak — never as a concentration.
Open the simulator03 · Titration planner
See the plan you were given.
Type in the titration from your prescriber — start, step, weeks per step, final dose, frequency, start date — and get a week-by-week table with dates and injection counts, the estimated curve over it, a print button and a link to share. It never proposes a dose or a step.
Open the plannerHow the level curve works
An estimate from published half-lives. Not a blood level.
Every dose you log is modelled as decaying by half every half-life. The curve is the running sum of what is left of each dose, sampled hour by hour, and scaled to the steady-state peak so it reads in percent.
level(t) = Σ dose × 2^(−(t − t_dose) ÷ half-life)
The half-life comes from the compound's published pharmacokinetics — the reference set lists its source for every value — and you can edit it. The model ignores absorption, distribution and individual variation, so it is an illustration of timing, never a measurement.
Estimate only. Modelled from the published half-life you selected and the doses you logged — not a measured blood level. Do not use it to make medication decisions.
Privacy
Your data lives on your device.
Everything you log is stored in an encrypted database on your device. No account is needed. Nothing is sent anywhere by default.
Sync is optional and user-scoped: sign in with an emailed code and your entries are stored for your account only, protected by row-level security, readable by you alone. Photos never leave your device, even when signed in.
No ad pixels, no analytics SDKs, no third-party scripts — in the app or on this site. STACK never sells data. The only thing this site can collect is an email address you type into the opt-in form, after you tick the consent box. Read the privacy policy.
Free vs Pro
Tracking is free. Pro is the analysis layer.
Free stays free — no trial that expires mid-protocol. Pro is $79/year, billed annually. See full pricing and FAQ →
| What | Free | Pro |
|---|---|---|
| Dose log, journal, site rotation, vials | Included | Included |
| Active protocols | 2 | Unlimited |
| Estimated-level curve | 7-day view | 7 / 30 / 90-day and all-time |
| Curve overlays across compounds | — | Included |
| Reminders | Before each dose | Smart, per-compound timing |
| Reconstitution calculator | Free on this site | In the app, saved to your vials |
| Clinician PDF report | — | Included |
| Optional account and sync | Included | Included |
Same STACK on every device you own. iPhone and Android apps are coming; the web app works on a phone today.
Start with your next dose.
Open STACK, add your protocol, log the next dose. Everything else follows from the log.