OptiPin
Free calculators
Sixteen free, no-login tools for TRT, peptides, and GLP-1, plus per-compound reconstitution guides. Every calculation can also be tracked and forecast over time in OptiPin.
Peptide Reconstitution Calculator
Enter vial size, BAC water, and target dose for the exact syringe units. 200+ medications, typical-dose hints, and one-tap blend expansion (GLOW, KLOW, Wolverine, and more).
Peptide Blend Calculator
Multi-compound stacks (Wolverine, GLOW, KLOW, GH Stack) - tap a preset or build your own and get the exact per-peptide syringe units.
Free Testosterone Calculator
Vermeulen equation - total T, SHBG, and albumin → free and bioavailable testosterone and percent free.
TRT Dose Calculator
Weekly dose + concentration + frequency → mL and insulin units per injection, and how long a vial lasts.
Half-Life Visualizer
Plot single-dose and steady-state blood-level curves for 60+ compounds, with time to peak and steady state.
Reverse Dose Calculator
Already drew it? Units back to milligrams, with a comparison against the dose you meant to take and a full units-to-mg chart.
Vial Transition Calculator
New vial at a different concentration - the units to draw for the same dose, how far off your old count would be, and splitting one dose across two vials.
Split Dose Calculator
Weekly to twice weekly, every other day or daily, holding the weekly total. Shows the per-injection dose, the units, and how much flatter your levels actually get for your compound's half-life.
HCG Dosage Calculator
Vial IU + bacteriostatic water + target dose → insulin units to draw, concentration, and doses per vial. Includes a full reconstitution and mixing chart.
Vial Longevity & Cost
Doses and weeks per vial plus cost per dose - works for peptides (total mg) or oil vials (size × concentration).
Insulin Syringe Units Chart
Units → mL → mcg. Why 1 unit is always 0.01 mL, the mcg-per-unit tables for every common reconstitution, and the U-40 warning.
Testosterone Unit Converter
ng/dL ↔ nmol/L (and E2, DHT, free T), with the CDC-harmonised reference range and guideline thresholds in both unit systems.
Peptide Storage & Shelf Life
How long peptides last as powder and reconstituted, why the 28-day figure is a preservative limit rather than a stability limit, and what actually degrades a peptide.
GLP-1 Titration Schedule
The standard manufacturer titration for Wegovy, Ozempic, and Mounjaro/Zepbound, mapped to dates from your start date.
GLP-1 Pen Click Charts
What a "click table" means and the click-to-mg mechanics for Ozempic and Mounjaro/Zepbound pens - plus why Wegovy has no clicks. Reference only.
Low Testosterone Quiz
10-question ADAM screening questionnaire - see whether your symptoms match the low-testosterone pattern. Educational, not a diagnosis.
Reconstitution guides by compound
The calculator handles any compound. These go deeper on one each: the water volume that actually suits its dose range, a full dose-to-units chart, and the specific way people get that compound wrong.
Semaglutide reconstitution
The whole 0.25–2.4 mg titration ladder in units, for 5 mg and 10 mg vials.
Tirzepatide reconstitution
10 to 60 mg vials, and the concentration a 15 mg dose needs to fit one syringe.
Retatrutide reconstitution
Dose-to-units for 5, 10, 12 and 30 mg vials, plus storage and beyond-use dating.
BPC-157 reconstitution
Microgram dosing, the mcg-to-mg conversion, and why it needs more water not less.
Tesamorelin reconstitution
Why the obvious 2 mg in 2 mL mix overflows a U-100 syringe.
HGH reconstitution
IU versus insulin units, the mg-to-IU conversion, and charts for every vial size.
NAD+ reconstitution
500 mg and 1000 mg vials, and why concentrating it matters more for comfort than for accuracy.
Track and forecast it all in OptiPin
Log doses, rotate sites, manage inventory, and forecast testosterone, estrogen & GLP-1 levels between blood draws - all on-device, no account required.
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