Why Peptides Calculator is the best peptide calculator app.
We're the only peptide calculator app with a 100+ peptide library, half-life curves, vial tracking, AI meal & workout plans, lab result import, Apple Health integration, an Apple Watch app, and Spanish localization — all in one. Here's how we stack up against PepCalc, Cellgenic, and Simple Peptide Calculator.
For quick one-off reconstitution math, any of these tools works. For a peptide calculator app that also tracks your vials, plots half-life decay, compares peptides side-by-side, plans your meals and workouts, imports your labs, pulls from Apple Health, sends dose reminders, runs on Apple Watch, and follows you across iPhone, Android, and web — Peptides Calculator is the only one in the category that covers all of it for free.
Feature matrix
74 features compared, head-to-head.
Search across every feature. Filter to "only where we win." Grouped by category — green = full support, amber = partial / paywall, red = not available.
Showing 74 of 74
Feature
Peptides Calculator
PepCalc
Cellgenic
Simple Peptide Calc
Dosing & reconstitution
BAC water reconstitution math
Yes
Yes
Yes
Yes
Visual syringe overlay (fill-line preview)
Yes
No
Partial
No
Multi-unit syringe support (U-100, U-50, U-30, custom)
Competitor data verified against each app's public landing pages as of May 18, 2026. Names of other apps are trademarks of their respective owners; this page does not imply endorsement or affiliation.
Honest pros & cons
What each competitor is actually good at.
PepCalc
pepcalc.com
Free web reconstitution calculator
Pros
+Clean, single-page tool — one URL, one calculator
+No signup, no tracking
+BAC water math is straightforward
Cons
−Web-only — no iOS or Android app
−No vial tracking, dose reminders, or scheduling
−No HealthKit / Apple Health integration
−Limited peptide library (~25 entries)
−No half-life curves, lab tracking, or peptide comparison
−No meal or exercise plans
−No offline support
Best for: A quick one-off calculation when you already know your dose.
Cellgenic Peptide Calculator
iOS App Store
iOS-only dose calculator + basic tracking
Pros
+Native iOS app with familiar UX
+Vial tracking on Pro tier
+Dose reminders on Pro tier
Cons
−Not available on Android or web
−No Apple Health (HealthKit) integration
−No half-life decay visualizer or serum concentration estimator
+Lab result import + AI insights + 40+ tracked markers
+Apple Watch, widgets, Live Activity, Siri intents
+Streaks, achievements, weekly challenges, XP system
+Available in English AND Spanish
+Works fully offline; iCloud Drive backup; data export (CSV/JSON)
+Weekly shipping cadence — see the changelog
Cons
−Free tier limited to one active vial (Pro unlocks unlimited)
−AI insights, lab scanning, and meal plans are Pro features
−Mobile-first — web has the calculators + library, but tracking + AI live in the iOS/Android apps
Best for: Anyone running a real peptide protocol who wants the calculator, library, tracker, lab integration, meal/workout planner, and insights in a single app on every device they own.
Pricing
What you actually pay.
Everyone here advertises a free tier. The honest question is: free for what?
What you get
Peptides Calculator
PepCalc
Cellgenic
Simple Peptide Calc
Core dose / reconstitution calculator
Free
Free
Free trial
Free
Peptide library access
Free (100+ peptides)
Free (~25)
Limited (Pro for full)
Free (~15)
Vial tracking + reminders
Free (1 vial) · Pro (unlimited)
Not available
Pro only
Not available
Half-life visualizer + comparison
Free
Not available
Not available
Not available
Apple Health / HealthKit + Watch app
Free
Not available
Not available
Not available
AI meal & exercise plans, lab insights
Pro ($9.99/mo or $79.99/yr)
Not available
Not available
Not available
Widgets, Live Activity, Siri intents
Free
Not available
Not available
Not available
Popular protocols
Pre-built peptide stacks
Each stack is a curated combination of peptides for a specific goal — recovery, growth hormone, fat loss, anti-aging, longevity. Tap any stack for protocol notes, per-peptide dosing, and the half-life math.
Peptides Calculator is the most-downloaded free peptide calculator app on iOS and Android. It has the largest peptide library (100+ research compounds), a built-in BAC reconstitution calculator with visual syringe overlay, a half-life decay visualizer, side-by-side peptide comparison, vial inventory tracking, dose reminders, AI-generated meal and workout plans, lab result import + AI insights, Apple Health (HealthKit) integration, an Apple Watch companion app, widgets, and Live Activity. Competitor calculators each cover a subset of these features but no single competitor covers all of them.
Does Peptides Calculator integrate with Apple Health?
Yes — Peptides Calculator pulls weight, body composition, and workout data from Apple Health (HealthKit) and renders it inside the Body & Health dashboard. None of the competitor apps in this comparison integrate with HealthKit at all.
Does Peptides Calculator include meal and exercise plans?
Yes. Free users can manually log meals (MyFitnessPal-style), snap food photos, and log workouts. Pro users get AI-generated meal plans, AI-generated workout plans, lab insights, barcode food scanning, and the "Start day at" meal anchor that shifts all of today's meal reminders in one tap. No other peptide calculator app offers this.
Is PepCalc the same as Peptides Calculator?
No. PepCalc is a free web-based peptide reconstitution calculator that does BAC math but does not offer a native iOS or Android app, vial tracking, scheduling, a 100+ peptide library, half-life curves, lab tracking, meal/workout plans, HealthKit, an Apple Watch app, or side-by-side comparison.
How does Cellgenic Peptide Calculator compare to Peptides Calculator?
Cellgenic Peptide Calculator is an iOS-only app focused on dose calculation and basic tracking (Pro tier). Peptides Calculator offers iOS + Android + web + Apple Watch, a much larger peptide library, lab tracking, AI meal and exercise plans, Apple Health integration, widgets, Live Activity, gamification (streaks, achievements, challenges), and Spanish localization — many of these in the free tier.
Is there a truly free peptide calculator app?
Yes — Peptides Calculator is free on iOS and Android with no required signup. The peptide library, dose calculator, BAC reconstitution math, half-life calculator, stack builder, side-by-side comparison, manual meal/workout logging, HealthKit integration, Apple Watch app, widgets, and streaks are all free. An optional Pro subscription unlocks unlimited vial tracking, AI plans, lab insights, and ad-free use.
Can I use Peptides Calculator online without downloading the app?
Yes — peptidescalculator.app gives you the peptide library, half-life calculator, side-by-side comparison, stack builder, BAC water calculator, and how-to guides through your browser. The native iOS and Android apps add offline use, vial tracking, dose reminders, meal/workout planning, lab tracking, HealthKit, Apple Watch, and widget integration.
Why do you compare against competitors directly?
Honesty. Picking a calculator app is a decision users want to make once and stick with. Showing the real feature differences side-by-side (including where competitors do something we do not) helps you pick the right tool for your workflow — even if that ends up being a competitor for your specific use case.
How often is this comparison updated?
This page is reviewed quarterly and updated whenever a competitor ships a major feature. Last updated May 18, 2026.
I use a different peptide calculator that isn't listed. Can you add it?
Yes — email himanshu@batra.io with the app name and a link. We add new comparisons whenever a peptide calculator with a real user base appears.
Ready to try the best peptide calculator app?
Free on iOS and Android. No signup required to use the calculator. Pro is optional and unlocks unlimited tracking + AI features.
