Head to head
PepCycle vs Glapp
Last reviewed · Written by the PepCycle team
Glapp's public presence leans heavily on GLP-1 calculators — dose conversion, split dosing, protein targets. PepCycle's calculators exist too, and are free on this site, but the product is the record: vials, schedules, sites and exports. A calculator answers a question once; a log answers questions you have not asked yet.
A calculator is not a log
Calculators are genuinely useful, which is why we publish eight of them free and unauthenticated. But a calculator has no memory. It converts numbers and forgets them, which means it can never answer the questions that matter later:
- What was my actual interval between injections over the last three months?
- Which sites have I used in the past two weeks?
- When did this side effect start relative to the dose change?
- How much is left in this vial, accounting for the entry I backdated?
Those require accumulated, structured history. Glapp's public positioning centres on GLP-1 calculators and conversion tools; PepCycle's centres on the record, with calculators as a component of it.
Our calculators are free and on the web
We took the view that calculation should not be behind a download, let alone a subscription. Everything on this site runs in your browser, sends nothing anywhere, and needs no account:
- Reconstitution calculator — vial mass and diluent volume to mcg per unit.
- Peptide unit converter — mg, mcg, mL and units, in every direction.
- Syringe unit converter — U-100, U-50 and U-40.
- Vial duration calculator — how many entries a vial has left.
- Bacteriostatic water calculator — work backwards from a target concentration.
- Cycle length planner — project an every-N-day schedule across a calendar.
What to test
- Can you keep a history, not just run a conversion?
- Does it handle lyophilised vials with a concentration you determine?
- Does it accept vial masses above 50 mg?
- Can you set an every-N-day schedule?
- Does backdating recalculate vial contents?
- Is there a complete export including concentrations?
- Where does the data live, and is an account required?
- When is the price shown relative to entering personal information?
Who each suits
- You want a quick conversion and nothing else: use our free tools, or any calculator you trust. No app needed.
- You want a record you can hand to a clinician: that is a log, and the export is the feature to evaluate.
- You take GLP-1 pens only: either may work — run the eight tests.
- You take pens and reconstituted vials: format-awareness is the deciding factor.
Frequently asked questions
Do I need to install an app to use PepCycle's calculators?
No. Every calculator on this site runs in your browser, requires no account, and sends nothing to a server. They are free to use whether or not you ever download the app.
What can a log do that a calculator cannot?
Answer questions retrospectively. A calculator converts a number now and forgets it; a log can tell you your actual injection intervals over three months, which sites you used recently, and when a side effect began relative to a dose change.
Is PepCycle a Glapp alternative?
They overlap on GLP-1 calculation. The difference in emphasis is that Glapp's public positioning centres on calculators and PepCycle's on the record, with calculators included. Check both current feature sets directly — this page reflects public information as of July 2026.
Related pages
Run the tests on us too
Download PepCycle and try the awkward cases yourself: a 200 mg vial, a three-peptide blend, an every-3-day schedule, and an entry backdated eleven days. That is a better evaluation than any comparison page, including this one.
Free to download · No account required · Price shown before you enter anything personal