--- title: "Peptide Calculator: Reconstitution & Dosage in Syringe Units" description: "Free peptide reconstitution calculator. Enter vial mg, mL of bacteriostatic water and your prescribed dose to see the units to draw on a U-100 insulin syringe." canonical: "https://www.vitalsvault.com/peptides/tools/dosage-calculator" last-updated: 2026-08-22 --- # Peptide Calculator: Reconstitution & Dosage in Syringe Units > Free peptide reconstitution calculator. Enter vial mg, mL of bacteriostatic water and your prescribed dose to see the units to draw on a U-100 insulin syringe. ![A Pacific Islander man, 46, broad, short grey-black hair, faint scar on chin reads the blank label on a small box at a bright counter](https://www.vitalsvault.com/_next/image?url=%2Fpublic-v3%2Fshoot%2Fpeptides%2Fhero-dosage-calculator.webp&w=3840&q=75&dpl=shadow-production-f0162cb4d465-40992538108-1) Peptide Guide · Free tools # Peptide dosage calculator Vial strength, water and the dose your clinician set in. The units to draw on a U-100 insulin syringe out. Works withAny peptide dosed in mg or mcg Syringes1 mL, 0.5 mL and 0.3 mL (U-100) CostFree, no sign-up ## Your result Draw to10units on a 1 mL U-100 insulin syringe (0.1 mL) Volume per dose0.1 mL Concentration2.5 mg/mL Each unit holds25 mcg Doses per vial20 The short answer To work out a peptide dose, divide the mg in the vial by the mL of water added to get the concentration, divide your dose by that concentration to get mL, then multiply by 100 for units on a U-100 insulin syringe. A 5 mg vial with 2 mL and a 250 mcg dose is 10 units. Medically reviewed by [Robert Lufkin, MD (opens in a new tab)](https://www.robertlufkinmd.com/) Chief Medical Officer, Vitals Vault · Updated October 29, 2026 · 5 sources This calculator converts a dose your clinician has already set into a syringe reading. It does not choose a dose, check whether a product is right for you, or replace your pharmacy’s instructions. Always follow the label and the clinician who prescribed it. ## Example setups Plain arithmetic, no peptide named. Tap a row to load it into the calculator. Example vial, water and dose combinations with the units to draw | Vial | Water | Concentration | Dose | Draw (U-100) | | --- | --- | --- | --- | --- | | | 2 mL | 2.5 mg/mL | 250 mcg | 10 units | | | 2 mL | 5 mg/mL | 500 mcg | 10 units | | | 1 mL | 2 mg/mL | 100 mcg | 5 units | | | 3 mL | 3.333 mg/mL | 1 mg | 30 units | | | 3 mL | 5 mg/mL | 2 mg | 40 units | ### Doses from FDA labels and studies in people We name a peptide here only when the dose, given as an injection under the skin, appears in an FDA label, a published human trial or a clinical practice report on that peptide’s profile. They are shown for education, not as a recommendation. Tap one to load the dose; your vial and water stay as entered. - Human trial · Injection under the skin Sermorelin0.5 mg Twice daily for 14 days Healthy men aged about 68; only the higher dose raised IGF-1 significantly. Studied as GHRH(1-29) [Source on the Sermorelin profile](https://www.vitalsvault.com/peptides/sermorelin#dosing) - Human trial · Injection under the skin Sermorelin1 mg Twice daily for 14 days Healthy men aged about 68; only the higher dose raised IGF-1 significantly. Studied as GHRH(1-29) [Source on the Sermorelin profile](https://www.vitalsvault.com/peptides/sermorelin#dosing) - Human trial · Injection under the skin Sermorelin2 mg Once nightly for 6 weeks 11 healthy, non-obese men aged 64 to 76 with low baseline IGF-1, self-injected at home; nightly growth hormone release rose, IGF-1 did not change [Source on the Sermorelin profile](https://www.vitalsvault.com/peptides/sermorelin#dosing) - FDA label · Injection under the skin of the abdomen Tesamorelin1.4 mg Once daily Egrifta SV; adults with HIV and lipodystrophy [Source on the Tesamorelin profile](https://www.vitalsvault.com/peptides/tesamorelin#dosing) - FDA label · Injection under the skin of the abdomen Tesamorelin1.28 mg Once daily Egrifta WR; adults with HIV and lipodystrophy. Not interchangeable with Egrifta SV [Source on the Tesamorelin profile](https://www.vitalsvault.com/peptides/tesamorelin#dosing) - Human trial · Injection under the skin Tesamorelin2 mg Once daily for 26 weeks Adults with HIV and excess abdominal fat; original formulation used in the phase 3 trial [Source on the Tesamorelin profile](https://www.vitalsvault.com/peptides/tesamorelin#dosing) - Clinical practice report · Injection under the skin Thymosin alpha-11.6 mg Twice a week; hepatitis B treatment courses of 6 or 12 months were reported Adults with chronic hepatitis B or C, the schedule used where the drug (Zadaxin) is approved outside the US [Source on the Thymosin alpha-1 profile](https://www.vitalsvault.com/peptides/thymosin-alpha-1#dosing) ## How the math works Three steps, the same for every peptide. Only the numbers on your label and prescription change. 1. 1. Concentrationvial mg ÷ water mL5 ÷ 2 = 2.5 mg/mL 2. 2. Dose in mgdose mcg ÷ 1,000250 ÷ 1,000 = 0.25 mg 3. 3. Volumedose mg ÷ concentration0.25 ÷ 2.5 = 0.1 mL 4. 4. Units (U-100)volume mL × 1000.1 × 100 = 10 units **Worked example.** A 5 mg vial mixed with 2 mL holds 2.5 mg, or 2,500 mcg, in every mL. A 250 mcg dose is 0.1 mL, which is 10 units on a U-100 insulin syringe. The vial holds 20 doses of that size. Units on an insulin syringe are a volume, not an amount of drug. One unit is 0.01 mL whatever is in the barrel, which is why the same 250 mcg can be 5 units in one vial and 25 in another. A milligram is 1,000 micrograms.[1](https://www.vitalsvault.com/peptides/tools/dosage-calculator#source-nist-si) If your label gives a concentration (for example 2.5 mg/mL) rather than a vial strength, the vial is already mixed. Enter the mg/mL figure as the vial amount and 1 mL as the water. ## Reconstituting a vial General education on how mixing usually works. Follow your pharmacy’s instructions; they override anything here. Many compounding pharmacies now ship peptides already in solution. If yours arrives as a powder, the label or the pharmacy’s insert says which diluent to use and how much. Sterile preparations are made and dated under the USP sterile compounding standard.[3](https://www.vitalsvault.com/peptides/tools/dosage-calculator#source-usp-797)[4](https://www.vitalsvault.com/peptides/tools/dosage-calculator#source-fda-503a) 1. 1Read the label firstCheck the peptide, the strength in mg, the diluent named, the beyond-use date and the storage line. If anything is unclear, call the pharmacy before mixing. 2. 2Use the diluent your pharmacy namesBacteriostatic water contains benzyl alcohol, which slows bacterial growth in a vial you puncture more than once. Some products need a different diluent.[2](https://www.vitalsvault.com/peptides/tools/dosage-calculator#source-dailymed-bwfi) 3. 3Keep it cleanWash your hands and wipe each rubber stopper with an alcohol swab, letting it dry. Use a new sterile syringe and needle for each step. 4. 4Add the liquid slowlyLet the diluent run down the inside wall of the vial rather than onto the powder. Swirl or roll gently until clear; shaking can damage some peptides. 5. 5Label and store itWrite the date you mixed it on the vial. Store it as the label says, usually in the fridge, and discard it by the beyond-use date. 6. 6Dispose of sharps safelyPut used needles and syringes straight into an FDA-cleared sharps container, never loose in the trash.[5](https://www.vitalsvault.com/peptides/tools/dosage-calculator#source-fda-sharps) ## Get the free Peptide Tracking Toolkit An Excel workbook that does the vial math, keeps your plan apart from what you actually took, tracks site rotation and flags dates to review, plus a short PDF guide for before you start. ### Workbook: 14 tabs - Start here - Dashboard - Vials - Schedule - Administration log - Site rotation - Wellness - Labs - Storage - Travel - Clinician questions - Provider and pharmacy - Costs - Notes ### Starter guide (PDF) - Still deciding, or already using one - FDA-approved, compounded and research-use, explained - Questions to ask a prescriber - How to read a compounding pharmacy label - Storage basics - Travelling with a prescription - Which labs to baseline, and when to retest ## Measure before you start The math tells you what to draw. Only a blood test before you start, and a retest after, shows what a peptide changed for you. 1. TestA baseline panel at Quest Diagnostics. 2. DecideA licensed clinician reviews your history and results. 3. RetestThe same markers again, side by side. [Start with 120+ lab tests · $99](https://www.vitalsvault.com/labs#plans) - [Liver enzymes (ALT)Checks the liver before and during any new prescription.](https://www.vitalsvault.com/biomarkers/alt) - [Kidney function (eGFR)Peptides are cleared through the kidneys, so a baseline is useful.](https://www.vitalsvault.com/biomarkers/egfr) - [HbA1cYour average blood sugar over about three months.](https://www.vitalsvault.com/biomarkers/hemoglobin-a1c) - [hs-CRPA blood marker of inflammation you can track before and after a course.](https://www.vitalsvault.com/biomarkers/hs-crp) ![A Latina woman, 36, petite, long chestnut braid, dimpled cheeks listens on a farmhouse porch](https://www.vitalsvault.com/_next/image?url=%2Fpublic-v3%2Fshoot%2Fpeptides%2Ffaq-dosage-calculator.webp&w=3840&q=75&dpl=shadow-production-f0162cb4d465-40992538108-1) ## Peptide calculator questions How do you calculate a peptide dose in units? Divide the mg in the vial by the mL of diluent to get mg per mL. Divide your prescribed dose (in mg) by that number to get mL, then multiply by 100 for units on a U-100 insulin syringe. 5 mg in 2 mL is 2.5 mg/mL, so a 250 mcg dose is 0.1 mL, or 10 units. What does reconstitution mean? Reconstitution means adding a sterile liquid to a freeze-dried powder so it becomes a solution you can draw into a syringe. The liquid and the amount come from the pharmacy that prepared the vial. How much bacteriostatic water should I add to a peptide vial? Add the amount on your pharmacy’s instructions. Many compounding pharmacies now ship vials already mixed. The volume itself is a convenience choice: more water makes each unit weaker and the draw larger, less water makes each draw smaller. It does not change how much peptide you receive. Why does adding more water change the units I draw? The peptide in the vial stays the same, but it is spread through more liquid. Double the water and every unit holds half as much, so you draw twice as many units for the same dose. How many units is 250 mcg? It depends on the concentration. In a 5 mg vial mixed with 2 mL, 250 mcg is 10 units. In a 10 mg vial mixed with 2 mL, it is 5 units. Enter your vial and water in the calculator above to get your number. How do I convert mcg to mg? Divide mcg by 1,000. 250 mcg is 0.25 mg, and 1 mg is 1,000 mcg. The calculator has an mcg and mg toggle, and the dose converter handles mcg, mg and IU. What is a U-100 insulin syringe? A U-100 syringe is marked so that 100 units equal 1 mL. One unit is 0.01 mL. The 1 mL, 0.5 mL and 0.3 mL sizes use the same scale; smaller barrels just have more room between marks, which makes small doses easier to read. Which syringe size should I use? Use the size your clinician or pharmacy supplies. As a rule, pick the smallest barrel that holds the whole draw: a 0.3 mL syringe for up to 30 units, 0.5 mL for up to 50 units, 1 mL for up to 100 units. What if my dose falls between two marks? The calculator shows the nearest mark and flags the gap. A smaller barrel often has finer marks. If you still land between marks, ask your clinician or pharmacist how to round, or whether a different dilution would make the draw land on a mark. Can I use this as a BPC-157 calculator? Yes. The arithmetic is the same for BPC-157, TB-500 and every other peptide: vial mg, water mL and dose. What differs is the dose, which a clinician sets. We name a peptide in the examples only when that dose, given under the skin, comes from an FDA label or a study in people. See the BPC-157 profile for the doses that have been studied. How long does a mixed peptide vial last? Use the beyond-use date on your pharmacy label. It depends on the peptide, the diluent and how the pharmacy prepared it, under the USP sterile compounding standard. Most mixed vials are kept in the fridge. Can I use sterile water or saline instead of bacteriostatic water? Only if your pharmacy says so. Bacteriostatic water contains benzyl alcohol, which slows bacterial growth in a vial you puncture more than once. Plain sterile water has no preservative, and some peptides need a specific diluent. Does this calculator tell me what dose to take? No. It converts a dose your clinician has already set into a syringe reading. Typical doses from FDA labels and studies in people are on each peptide’s profile, for education. Your dose should come from a licensed clinician who knows your history and labs. Where does the amount in my vial come from? From the label. A compounding pharmacy label lists the strength, such as 5 mg per vial or 2.5 mg per mL. If the label shows mg per mL, the vial is already mixed: enter that concentration as the vial mg with 1 mL of water. ## Peptides, prescribed and measured Vitals Vault is opening peptide care that starts with your blood work, is prescribed by licensed US clinicians and ends with a retest. Join the waitlist to hear first. - Prescription only - Licensed US clinicians - Quest Diagnostics labs [Get early access to peptide care](https://www.vitalsvault.com/peptides-waitlist)[Start with 120+ lab tests · $99](https://www.vitalsvault.com/labs#plans) ## More peptide tools - [Peptide dose convertermcg to mg, and IU where a fixed standard exists.](https://www.vitalsvault.com/peptides/tools/dose-converter) - [Peptide Tracking ToolkitFree Excel tracker and a starter guide (PDF).](https://www.vitalsvault.com/peptides/tools#toolkit) - [Peptide GuideWhat each peptide is, what it is studied for, and typical doses in people.](https://www.vitalsvault.com/peptides) ## Keep reading [Full Peptide Guide](https://www.vitalsvault.com/peptides) - SermorelinA 29-amino-acid fragment of growth hormone releasing hormone, once FDA-approved as Geref and since discontinued. - TesamorelinAn FDA-approved growth hormone releasing factor analog (Egrifta) for excess abdominal fat in adults with HIV-associated lipodystrophy. - Thymosin alpha-1A 28-amino-acid thymus peptide approved abroad for hepatitis B and C and studied as a vaccine adjuvant and in sepsis. - BPC-157A 15-amino-acid peptide from a stomach protein, studied for tendon, muscle and gut repair. ## Sources 1. 1. [NIST. Metric (SI) prefixes (opens in a new tab)](https://www.nist.gov/pml/owm/metric-si-prefixes) 2. 2. [DailyMed (NLM). Bacteriostatic Water for Injection, USP: product labels (opens in a new tab)](https://dailymed.nlm.nih.gov/dailymed/search.cfm?labeltype=all&query=bacteriostatic+water+for+injection) 3. 3. [USP General Chapter <797> Pharmaceutical Compounding: Sterile Preparations (opens in a new tab)](https://www.usp.org/compounding/general-chapter-797) 4. 4. [FDA. Bulk drug substances used in compounding under section 503A (opens in a new tab)](https://www.fda.gov/drugs/human-drug-compounding/bulk-drug-substances-used-compounding-under-section-503a-fdc-act) 5. 5. [FDA. Safely using sharps (needles and syringes) at home, at work and on travel (opens in a new tab)](https://www.fda.gov/medical-devices/consumer-products/safely-using-sharps-needles-and-syringes-home-work-and-travel) Built by the Vitals Vault editorial team, medically reviewed by Robert Lufkin, MD, and updated October 29, 2026. General education, not medical advice. This calculator converts a dose your clinician has already set into a syringe reading. It does not choose a dose, check whether a product is right for you, or replace your pharmacy’s instructions. Always follow the label and the clinician who prescribed it. --- Canonical HTML: https://www.vitalsvault.com/peptides/tools/dosage-calculator - [llms.txt](https://www.vitalsvault.com/llms.txt) - [sitemap.xml](https://www.vitalsvault.com/sitemap.xml) - [Developer portal](https://www.vitalsvault.com/developers)