Guides/Free Peptide Calculator
Free — v3.1.0

The Best Peptide Calculator Is Free

As of v3.1.0, Protocol's peptide calculator is free for all users — no Pro subscription required. Here's what you get and how it compares to paid options like PepCalc.

Protocol vs PepCalc

PepCalc is a $9.99 standalone peptide calculator. Protocol includes a more capable calculator for free — built into a full protocol tracking app.

FeatureProtocolPepCalc
PriceFree$9.99 one-time
PlatformiOS + AndroidiOS only
Standard reconstitution calc✅✅
Custom Draw mode✅❌
Saves vial history✅❌
Dose tracking✅❌
Low-stock alerts✅❌
Injection site tracker✅❌
Compound library (81 profiles)✅❌
AI research assistant✅❌
No account required✅✅
On-device only (private)✅✅

What Changed in v3.1.0

Before v3.1.0, the peptide calculator in Protocol was part of the Pro feature set. Starting with v3.1.0, the calculator became completely standalone — available to every user who downloads the app, with or without a Pro subscription.

The full calculator — including Custom Draw mode, all 81 compound profiles, concentration slider, and doses-per-vial calculation — is now free. Pro remains available for protocol tracking, Stack Score, interaction checker, bloodwork logging, and the AI research assistant.

The decision was simple: reconstitution math shouldn't be paywalled. Protocol's calculator — including Custom Draw mode — should be free.

Custom Draw Mode: The Feature PepCalc Doesn't Have

Every other peptide calculator works the same way: enter your vial size and BAC water volume, get back concentration and draw units. Protocol's Custom Draw mode works backwards — enter your preferred draw amount first and get the exact BAC water to add.

Try the Free Calculator →

FAQ

Is there a free peptide calculator?+
Yes. Protocol's peptide calculator is completely free as of v3.1.0 — no Pro subscription required. Download the app on iOS or Android and the full calculator, including Custom Draw mode, is available immediately with no paywall.
How does Protocol compare to PepCalc?+
Protocol's calculator is free (PepCalc costs $9.99 one-time). Protocol also includes Custom Draw mode — enter your preferred syringe units and get the exact BAC water volume to add — which PepCalc does not have. Protocol saves vial history, tracks doses, and sends low-stock alerts. PepCalc is a standalone calculator only.
What is Custom Draw mode?+
Custom Draw mode lets you specify your preferred syringe draw amount first — say, 10 units on a U-100 syringe — and the calculator tells you exactly how much BAC water to add to achieve that draw for your target dose. Most calculators only work in the other direction.

Download Protocol — Free

iOS + Android. Full calculator free in v3.1.0. 14 days Pro at install.

Download on the App StoreGet it on Google Play