Stop guessing what is in the syringe.
PepStepper does the reconstitution maths, converts it to the marks on the barrel you actually own, and tells you which runs out first — the pep or its fridge life.
Works on your phone and your laptop, which is the point — entering a protocol is a desktop job and logging a dose is a phone job, and nothing else in this category does both.
I want this dose — how far do I fill?
Draw to 5 units
50 µL on a U-100 barrel
- Concentration
- 5 mg/mL
- One unit is
- 0.05 mg
- Doses in the vial
- 40
Free, no signup. This runs entirely in your browser — nothing you type here is sent anywhere or stored, by us or by anyone else.
Your vial has 12 doses left. You will only use seven.
Doses-remaining is the number every tracker shows, and on its own it is misleading. The pep runs out on one date and its beyond-use date arrives on another, and the earlier of the two is the one that governs.
PepStepper tells you which, how many doses you actually get before it, and what the leftover cost you.
The beyond-use date lands eleven days first. You get 7 doses, not 12.
$120
of retatrutide would go unused. Knowing that on 5 September is the difference between mixing 3 mL and mixing 1.75 mL.
Four things, in the order you actually do them.
You type what you have. It does the arithmetic. It never picks a number for you.
Reconstitute
Tell it what went in the vial
10 mg of powder, 2 mL of bacteriostatic water. It works out the concentration and holds onto it — the vial you mixed in July is still 5 mg/mL in October, whatever you have edited since.
Draw
It converts to the marks on your barrel
Your dose in milligrams, its position on the barrel you actually own, and what that mark really delivers when it does not land exactly. U-40 gets a blocking warning, not a toast.
Log
One tap, with the site you used
The drawn volume is what gets stored, never a rounded milligram figure — so the number on screen and the number in your history can never drift apart. Injection sites track across every compound at once.
Know
And which runs out first
Doses left, the date the vial empties, the date its fridge life ends, and which of those two arrives sooner. That last one is the question nothing else in this category answers.
What you run is nobody else’s business.
Every app in this category says something like this. Here is what it means concretely, so you can check it.
- No analytics on any page that shows your data
- Tracking scripts are not shipped with the app. It is a separate deployment that does not contain them, so this is a fact about the bundle rather than a promise about our intentions.
- Reminders do not name the compound
- By default a notification says “you have a dose due”. Naming it on a lock screen tells whoever is standing nearby, and in an email it tells your mail provider.
- Progress photos expire in 60 seconds
- They live in a private bucket only your account can read, shown through links that are dead within the minute. A URL copied out of the page is worthless.
- Delete means delete
- Your rows, your photos, your account. Not deactivated — removed, and the deletion refuses to run at all if it cannot take the files with it.
- This calculator stores nothing
- What you typed above never left your browser. No account, no cookie, no request.
- Export whenever, subscription or not
- Your log stays yours if you cancel. Holding data hostage is how a company earns a chargeback.
Referrals
Bring people in.
Get paid for it.
Everyone running a protocol knows three other people doing the same thing. Send them your link and you earn on every one who stays — as credit against your own bill, or as money you can withdraw.
Monthly
$5
They pay $9.99 a month
Annual
$15
They pay $79 a year
Founding member
$30
They pay $149 once
Paid when they pay
Not at signup, and not for a trial that never converts. The reward lands when their first real payment does — which is also why the numbers can be this size.
Cash out from $10
Take it as credit and it comes off your next invoice automatically. Or connect a payout account through Stripe and withdraw it once your balance reaches $10.
Your link keeps working
It remembers them for 90 days. Someone who opens it today, thinks about it, and signs up next month still counts as yours.
No cap on how many
There is no ceiling on referrals. A large banked balance routes to the cash side rather than sitting as credit you could never spend.
Your link works from the moment you sign up — trial or not.
One plan. Everything in it.
No tiers, no feature gates, no “upgrade to see your own history”. Seven days free with a card up front, and cancelling takes two clicks.
Bring someone in and you earn credit once they actually become a paying customer — never at signup, and never for a trial that does not convert. It comes off your next invoice automatically.
Questions people actually ask.
Does it tell me what dose to take?
Does it work on a phone?
What is reverse mode?
Can it handle blends?
What happens to my data if I stop paying?
Do you sell anything, or link to anywhere to buy?
Where is my data stored, and who can see it?
Is this medical advice?
Every Pep. For Every Step.
7 days free. Card up front, cancel in two clicks, and your log exports whether you stay or not.
Start tracking properlyOr just use the calculator — it is free and it always will be.