Peptide Calculator

Injectable + Oral Equivalent

Use our calculator to accurately determine dosing for both oral and injectable peptides — fast, simple, and reliable.

How does it work

*Educational tool only. Not medical advice. For research purposes. Not for human consumption.

1.

Select or input peptide

Select a peptide to see details.

2.

Desired dose per injection

0.1 mg = 100 mcg (μg)
Common doses: 250 mcg, 500 mcg

3.

Total peptide content in vial (mg)

Common vial sizes: 2mg, 5mg, 10mg — check your label

4.

Bacteriostatic water (ml)

Typically 1–3 ml. Use less for higher concentration

Result

Complete all steps to see results

Peptide dose —
Your Vial Contains —
Solution Concentration —
10 20 30 40 50 60 70 80 90 100
Draw to — units
—

Equivalent Oral Dose

Oral Dose —
Frequency —
Delivery System —

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Oral bioavailability is significantly lower than injection. This range accounts for the absorption difference.

STEP 4: FIND A TRUSTED SUPPLIER

You've found your dose.
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Peptide Dosage Calculator FAQs

What is a peptide dosage calculator and how does it work?

A peptide dosage calculator takes 4 inputs and gives you an exact dose you can measure. Peptides are short chains of amino acids, and getting the dose right starts with a little math the tool handles for you.

  1. Select your peptide or enter a custom compound.
  2. Choose your desired dose (common doses are 250 mcg and 500 mcg).
  3. Enter your total peptide vial content (common sizes are 2 mg, 5 mg, and 10 mg).
  4. Set your bacteriostatic water volume in milliliters (typically 1 to 3 mL).

It returns your solution concentration, draws volume in insulin syringe units, and the equivalent oral dose. That way you can compare both routes side by side without doing the reconstitution math yourself.
What is the oral equivalent dose feature?

Most calculators only handle injectable dosing. Ours also shows you the equivalent oral dose, so you can skip the needle and still know exactly how much to take.

Oral peptides remove the hardest parts of the process: no peptide reconstitution, no bacteriostatic water, no insulin syringe, no injection. Injectable peptides absorb at close to 100% bioavailability, while oral absorbs at a lower rate, so the calculator adjusts the oral dose in micrograms to match. Here is how absorption differs by route in this look at BPC-157 oral bioavailability.
What are common peptide dosing mistakes to avoid?

Getting the concentration right is the foundation. You find it by dividing the total peptide in your vial (in mg) by the water volume you added (in mL). A few errors show up more than others:

  • Confusing mg and mcg. This creates a 1,000x dosing error. Remember that 1 mg equals 1,000 micrograms.
  • Wrong reconstitution volume. Adding 1 mL vs. 2 mL to the same peptide vial changes your whole concentration. More water spreads out the solution and makes small doses easier to measure.
  • Misreading syringe units. They are volume marks, not dose marks, and only mean something once you know your concentration.
  • Skipping titration. Start low and build over 1 to 2 weeks to avoid early side effects.

Oral formats remove most of these risks, since there is no reconstitution math or insulin syringe involved.
How should I store peptides?

Oral capsules and topical serums are easiest, since most are shelf-stable at room temperature. Refrigeration can extend potency, so read and follow the label.

Injectable peptides need more care for proper storage:

  • Store the reconstituted solution at 2 to 8°C and use within 28 days.
  • Gently swirl before each draw and never shake.
  • Keep vials out of light, and do not freeze and thaw repeatedly.

Peptide powder is more forgiving. In its unreconstituted, lyophilized form it can last 1 to 2 years when refrigerated.
Do peptides have side effects or interact with medications?

Peptides are generally well tolerated, and most reported side effects are mild and dose-dependent. The most common are minor GI discomfort, headache, or temporary water retention. Injectable users sometimes notice redness at the injection site, which oral capsules and sprays avoid.

Peptides can interact with medications that affect blood sugar, blood pressure, or thyroid function. Share your full medication list with a healthcare provider before starting, and choose third-party tested products with a certificate of analysis.
Can I stack peptides, and which combinations work together?

Yes. Many people combine peptides that target different goals, since each works through its own pathway. A few well-documented pairings from our list:

  • BPC-157 + KPV: Tissue and gut repair plus anti-inflammatory support.
  • BPC-157 + GHK-Cu: Recovery support plus collagen and skin benefits.
  • BPC-157 + TB-500: Focused on tissue repair and recovery.

One note for injectable users: do not mix two peptides in the same vial or syringe, since they can lose stability. Oral and topical formats avoid this entirely. You can find more pairings in this guide to peptide stacking for recovery.
Is this peptide calculator free, and do I need to sign up?

Yes. The calculator is completely free with no signup needed. Enter your inputs to calculate peptide dosage and get instant results.

If you want a certified oral or topical peptide, the "Get Recommendation" button connects you with tested options ready to use.
How much GHK-Cu should I take?

It depends on the format. Topical serums and creams are the most common choice, applied once or twice daily to clean skin.

For topical use, you apply a thin layer by pump or drop instead of measuring milligrams. If your skin is new to copper peptides, start every other day and build to daily. Oral GHK-Cu capsules are also available, and you just follow the label. Topical GHK-Cu can be used continuously for skin rejuvenation and does not need a break, as covered in this guide to GHK-Cu for firmer skin.
Is GHK-Cu better for skin or hair, and how long until it works?

GHK-Cu works for both. For skin, a topical serum supports collagen and elastin for firmness and texture. For hair, topical products applied to the scalp are the practical at-home option.

Results build slowly. Many people notice skin changes within a few weeks, with the biggest improvements after a few months of consistent use. More on what it does is in this overview of GHK-Cu peptide benefits.
How much BPC-157 should I take per day?

Commonly referenced amounts sit around 250 to 500 mcg per day, adjusted for your goal and body size.

BPC-157 stays stable in stomach acid, which makes oral capsules and sprays a practical option, especially for gut goals where it acts right where you want it. If you are mixing an injectable vial, a common question is how much bacteriostatic water to add to a 10 mg vial, and the calculator handles that step for you. Because oral absorption is lower than injection, oral doses are usually set higher to compensate, as this BPC-157 dosage guide explains.
BPC-157 oral vs injection, which is better?

Both work. The choice comes down to your goal and how hands-on you want to be.

Injectable delivers the highest absorption and is often used near a target area. Oral is the simpler route, with no mixing and no needles. For gut goals, oral is a strong pick because BPC-157 survives stomach acid and acts directly in the digestive tract. The full comparison of BPC-157 oral vs injection covers each use case.
What is the correct KPV dosage?

Commonly referenced KPV peptide dosage sits around 200 to 500 mcg per day, usually taken once daily on an empty stomach.

Oral KPV is often preferred for gut and IBD goals. It is absorbed through a transporter called PepT1, which is more active in inflamed gut tissue, so oral KPV concentrates right where inflammation is highest. Route-by-route detail is in this KPV peptide dosage guide.