Peptide Dose Calculator: Free, No Sign-Up
Reconstitution math, exact draw volume, and pharmacokinetic simulation for 330 compounds, every peptide, anabolic, SERM, AI, and GLP-1 agonist you'd inject. No ads, no paywall, no account required.
Run this calculation in VitaLog
Live peptide dose + reconstitution calculator. No sign-up to try. Sign up free to save your protocol, get draw-day reminders, and correlate dose against your bloodwork.
Open peptide dose calculator Explore the demo firstHow to use the calculator, in 30 seconds
Three inputs, one calculation. Every field has a sensible default; tap to edit.
- Vial size (mg). The total peptide mass printed on the vial, not the dose you intend to inject. Typical sizes: 2 mg, 5 mg, 10 mg. For GLP-1 vials the label may read in mg or in IU; see the unit-conversion table below.
- Reconstitution volume (mL). The amount of bacteriostatic water you added to the vial to dissolve the peptide. More water = lower concentration = larger draw volume per dose. Common choices: 1 mL, 2 mL, 3 mL, or 5 mL.
-
Target dose (mcg or mg). The dose you intend to inject. VitaLog returns the exact volume in
mLand in U-100 insulin-syringeIUticks, and simulates the serum concentration curve.
Worked example, BPC-157 at 250 mcg/day
Take the most common scenario: a 5 mg BPC-157 vial reconstituted with 2 mL of bacteriostatic water, dosed at 250 mcg per injection.
Concentration = vial_mg / reconstitution_mL
= 5 mg / 2 mL
= 2.5 mg/mL
= 2500 mcg/mL
Draw volume = target_dose / concentration
= 250 mcg / 2500 mcg/mL
= 0.1 mL
= 10 IU on a U-100 insulin syringeVitaLog then simulates the serum curve using a one-compartment first-order absorption model (Bateman): given BPC-157's estimated absorption rate and elimination rate, you'll see Cmax ≈ minutes after subcutaneous injection and a terminal half-life in the low hours (extrapolated from animal studies; no human PK published).
dataQuality: extrapolated so you can tell which numbers are published vs. inferred.
Supported compound classes
Peptides
BPC-157, TB-500, CJC-1295 (with/without DAC), ipamorelin, sermorelin, MK-677, MOTS-c, GHK-Cu, melanotan II, epitalon, tesamorelin.
GLP-1 agonists
Semaglutide, tirzepatide, retatrutide. Weekly subcutaneous dosing, standard titration schedules built in.
Testosterone esters
Cypionate, enanthate, propionate, phenylpropionate, undecanoate (IM + oral), suspension. Two-compartment kinetics supported for suspension.
Other anabolics
Nandrolone decanoate/phenylpropionate, boldenone undecylenate, masteron E/P, primobolan E/A, trenbolone A/E/Hex, trestolone acetate (MENT).
Orals (17-α-alkylated)
Anavar (oxandrolone), winstrol (stanozolol), dianabol (methandrostenolone), anadrol, turinabol, proviron, halotestin.
AIs + SERMs
Anastrozole, exemestane, letrozole (AIs). Tamoxifen, clomiphene, raloxifene (SERMs), PCT planner built in.
Unit-conversion cheat-sheet
| From | To | Formula | Example |
|---|---|---|---|
| mg | mcg | × 1000 | 5 mg = 5000 mcg |
| mcg | mg | ÷ 1000 | 250 mcg = 0.25 mg |
| mL | IU (U-100 insulin syringe) | × 100 | 0.1 mL = 10 IU |
| IU (U-100) | mL | ÷ 100 | 10 IU = 0.1 mL |
| Dose (mcg) | Volume (mL) | ÷ concentration (mcg/mL) | 250 mcg ÷ 2500 mcg/mL = 0.1 mL |
| Concentration (mg/mL) | Concentration (mcg/mL) | × 1000 | 2.5 mg/mL = 2500 mcg/mL |
What the PK simulation shows
After the dose math, VitaLog plots the expected serum-concentration-vs-time curve using the compound's kinetic parameters. Four models are supported:
-
One-compartment Bateman: the workhorse for most peptides and subcutaneous anabolics. Formula:
C(t) = (F·D·ka / V·(ka − ke)) · (e^(−ke·t) − e^(−ka·t)), with L'Hôpital's rule applied when the absorption and elimination rates approach each other. - Two-compartment: for testosterone base/suspension where biphasic distribution between blood and tissue matters. Roots (α, β) solved analytically.
- Biphasic absorption (one-compartment sum): for depot formulations such as nandrolone decanoate with distinct fast and slow absorption phases.
- Metabolite cascade: convolves a parent-drug profile as the input to a metabolite's one-compartment model (for example, testosterone → DHT).
Every simulation carries a P25–P75 variability envelope computed from the compound's log-normal CV of absorption, clearance, and volume of distribution. Cmax, Tmax, AUC, accumulation ratio (1 / (1 − e^(−ke·τ))), and days-to-steady-state (5 × t½) are annotated on the chart.
Related free tools in VitaLog
- Vermeulen free testosterone calculator: compute free and bioavailable testosterone from total T, SHBG, and albumin using the 1999 quadratic.
- PCT planner: compute the earliest PCT start date from a compound's terminal half-life and the SERM dose schedule for tamoxifen / clomiphene / raloxifene.
- Bloodwork trend analyzer: import two or more panels; VitaLog detects rising/falling markers, persistently-high values, hematocrit-cap alerts, and AST/ALT-ratio patterns with age- and sex-indexed reference ranges.
- BPC-157 reconstitution how-to: step-by-step guide with a dose chart. Read the guide →
- TRT bloodwork monitoring: the full panel, frequency, interpretation rules, and red flags. Read the guide →
Frequently asked questions
- What units does the peptide dose calculator use?
- Vial size in mg, reconstitution volume in mL, target dose in mcg or mg. Output is in mL and in U-100 insulin-syringe units (IU), where 1 IU = 0.01 mL on a U-100 syringe.
- Is the calculator free?
- Yes. No account, no paywall, no ads. The calculator works offline in the installable VitaLog PWA or online in any modern browser.
- Which peptides does it support?
- BPC-157, TB-500 (thymosin beta-4), CJC-1295 (with or without DAC), ipamorelin, sermorelin, MK-677, MOTS-c, GHK-Cu, melanotan II, epitalon, and other common research peptides. GLP-1 agonists (semaglutide, tirzepatide, retatrutide) are also supported.
- How do I convert mcg to IU on an insulin syringe?
- On a U-100 insulin syringe, 1 IU tick equals 0.01 mL. So if your concentration is 2500 mcg/mL (5 mg vial + 2 mL BAC water) and your dose is 250 mcg, the volume is 0.1 mL, that is 10 IU on a U-100 syringe.
- Does this give medical advice?
- No. VitaLog is an educational and harm-reduction tool. It does not diagnose, treat, or prescribe. Consult a qualified healthcare professional before making any medication or dosing decision.
- Does the calculator show a PK simulation?
- Yes. After computing the draw volume, VitaLog shows the expected serum concentration curve using the appropriate pharmacokinetic model, one-compartment Bateman for most peptides, two-compartment for testosterone suspension, biphasic absorption for depot formulations.
- Can I use this for testosterone esters like cypionate?
- Yes. VitaLog supports all testosterone esters (cypionate, enanthate, propionate, phenylpropionate, undecanoate, suspension) with ester-fraction conversion to free testosterone and appropriate half-life modeling for each.
- Does it work for semaglutide and tirzepatide?
- Yes. Enter vial mg + BAC water mL + target weekly dose; VitaLog returns draw volume, standard-titration recommendations, and a weekly-trough PK simulation at steady state.
- How accurate is the reconstitution math?
- The math is exact: concentration = mg / mL, dose volume = dose / concentration. Rounding is handled to the nearest 0.005 mL (0.5 IU on U-100) to match the finest visible graduation on standard insulin syringes.
- Can I save my protocol for next time?
- Yes, create a free VitaLog account and your compound library, dose schedule, injection-site rotation, and cycle logs persist across devices with zero-knowledge encryption.
Track this with your protocol
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