Peptide Calculator

Calculation Mode:

Vial Size (mg)

Water Volume (ml)

Weight-Based Dose?

Desired Dose (mcg)

Syringe Size (ml)

Cycle Days (Optional)

Result:

Step 1: Choose Your Calculation Mode
Mode 1: Find Units to Inject

Use this when: Your doctor told you to take a specific dose (e.g., "take 250 mcg")
Calculator tells you: How many units to pull on your insulin syringe

Mode 2: Find My Dose

Use this when: Your doctor told you to inject a specific number of units (e.g., "inject 20 units")
Calculator tells you: The actual dose you're getting in mcg/mg
Step 2: Enter Your Information
A. Select Syringe Size
Choose your insulin syringe size:

0.3ml = 30 units
0.5ml = 50 units
1.0ml = 100 units (most common)

B. Peptide Vial Size
Enter the amount of peptide in your vial:

Click a preset button: 5mg, 10mg, 15mg, 20mg, 50mg
OR type a custom amount in the box below

C. Bacteriostatic Water Amount
Enter how much water you're adding to reconstitute:

Click a preset: 1ml, 2ml, 3ml, 5ml
OR type a custom amount
Step 3: Enter Dose Information
If Using Mode 1 (Find Units):
Option A: Direct Dose Entry

Click a preset dose: 50mcg, 100mcg, 250mcg, 500mcg
OR type your custom dose in mcg

Option B: Body Weight-Based Dosing

Check the box: "Calculate dose based on body weight"
Enter your body weight in kg
Enter the dose per kg (your doctor should provide this)
Calculator automatically computes your total dose

If Using Mode 2 (Find Dose):

Simply enter the number of units your doctor prescribed
Step 4: Read Your Results
Mode 1 Results Show:

Your Dose: Confirms your dose in mcg
Draw Syringe To: The exact units to pull (this is what you need!)
Visual Syringe: Shows where to pull on the syringe
Concentration: How strong your mixture is (mg/ml)
Per Unit: How many mcg are in each unit

Mode 2 Results Show:

Units Prescribed: Confirms the units
Your Actual Dose: The real dose in mcg and mg
Concentration: How strong your mixture is

Per Unit: How many mcg per unit
Optional: Cycle Planning
Enter the number of days in the "Cycle Length" field to calculate:

Total peptide needed for your entire cycle
Helps you know how many vials to order

Warnings
The calculator will warn you if:

Your dose exceeds your syringe capacity
You need a larger syringe or need to adjust your water amount
Warnings
Describe the item or answer the question so that site visitors who are interested get more information. You can emphasize this text with bullets, italics or bold, and add links.
Example Walkthrough
Scenario: Doctor prescribed 250 mcg of BPC-157 daily

Mode: Select "Find Units to Inject"
Syringe: Click "1.0ml" (100 units)
Vial: Click "5mg"
Water: Click "2ml"
Dose: Click "250mcg"
Result: Calculator shows "Pull to: 10 units"
Action: Draw your insulin syringe to the 10-unit mark

Quick Tips

✅ Always double-check your inputs before injecting

✅ Consult your healthcare provider with any questions

✅ Use the visual syringe as a reference guide

✅ The common peptide dosages section shows typical doses for reference

✅ If using custom amounts, make sure to enter the correct units (mg for vial, ml for water, mcg for dose)

Understanding how peptide dosing works is critical before using any calculator. The calculator simply converts concentration into a measurable syringe volume.

If you want to understand the math behind peptide dosing, including micrograms, milligrams, and syringe units, read the full guide on peptide dose calculation explained.

Common Reconstitution Volumes

While almost any volume of bacteriostatic water can be used, a few common amounts make dosing easier depending on the situation:

2 mL (Most Common) – A balanced option that works well for most peptides. It keeps concentrations manageable while maintaining reasonable injection volumes and is commonly used with standard 5 mg vials.
1 mL (Higher Concentration) – Produces a stronger solution and smaller injection volumes. This approach can make precise dosing slightly more difficult for beginners.
3 mL (Lower Concentration) – Creates a more diluted solution, which can make small dose adjustments easier but results in larger injection volumes.

For most people working with a standard 5 mg peptide vial, starting with 2 mL of bacteriostatic water provides a practical balance between concentration and dosing accuracy.

Want a full walkthrough of how to reconstitute peptides safely?

Read the complete guide:

Peptide Reconstitution Guide

My calculator result shows more units than my syringe holds
You've likely used too much bacteriostatic water for your desired dose. Reconstitute with a smaller volume (try 1ml instead of 2ml) to create a more concentrated solution.
The numbers seem too small (2-3 units)
Very small measurements are difficult to draw accurately. Consider using less water during reconstitution to achieve a higher concentration, making your target dose correspond to a larger, more measurable number of units.
I'm getting different results from different calculators
Verify that all inputs are in the same units. Check that you're comparing calculations for the same reconstitution volume and syringe type. If discrepancies persist, work through the math manually using our formula above.
My reconstituted peptide looks cloudy
This isn't a calculation issue, but it indicates a problem. Peptide solutions should be clear. Cloudiness may indicate contamination, incorrect reconstitution, or degraded peptide. Do not use cloudy solutions.
I forgot how much water I added to my vial
Unfortunately, you cannot accurately calculate dosing without knowing the reconstitution volume. It's safer to discard the vial and start fresh with documented measurements than to risk incorrect dosing.

Learn How to Store Peptides After Reconstitution

Proper storage plays a major role in maintaining peptide stability after mixing. Temperature, light exposure, and handling practices can all affect how long a peptide remains viable.

For a complete guide on refrigeration, freezing, and stability timelines, see:

Peptide Storage After Reconstitution

Understanding Bacteriostatic Water

Peptide calculators rely on concentration, which is created when bacteriostatic water is added during reconstitution. The volume of BAC water determines the final peptide strength used in all dosage calculations.

If you want a deeper explanation of how bacteriostatic water works and why it is used for peptide mixing, read:

Bacteriostatic Water for Peptides

Project Biohacking's Peptide Calculator App

Accurate and Convenient Calculations On the Go

The Peptide Calculator app is designed to offer researchers, lab technicians, and compounders a simple yet powerful tool for calculating peptide dosages, molecular weights, dilution volumes, and reconstitution values wherever and whenever needed.

User-Friendly Interface

With an intuitive layout and streamlined navigation, the app saves time by eliminating the need for complex manual calculations. Whether you're working with milligrams, micrograms, or nanograms, the calculator adapts to your workflow efficiently.

Key Features

✔ Peptide Reconstitution: Instantly determine how much bacteriostatic water or diluent to add.

✔ Dosage Calculation: Calculate dosage per body weight, injection volume, or concentration.

✔ Unit Conversion: Seamless conversion between units such as mg/mL, IU, and more.

Perfect for Research and Clinical Use

Whether you’re conducting peptide-based research or preparing formulations for clinical studies, the Peptide Calculator app ensures precise results every time, reducing human error and improving consistency in your protocols.

Available for iOS and Android

Peptide Calculator Best Practices

Understanding Peptide Dosage Calculations

A peptide calculator converts concentration into a measurable syringe volume. The accuracy of the result depends entirely on the concentration created during reconstitution and the dose entered.

If you want to understand the math behind peptide dosing including micrograms, milligrams, and syringe units — read the full guide:

Peptide Dosage Calculation Guide

Quality Matters: Source from Verified Vendors

Calculations only work when your peptides contain the labeled amount of active compound. We've vetted suppliers who provide:

Third-party testing certificates (COA)
Proper labeling and documentation
Appropriate storage during shipping
Clear expiration dates

Browse trusted peptide vendors with exclusive Project Biohacking discount codes, or compare quality standards across Limitless Biotech, Biolongevity Labs, CanLab, and Rejuvatide Peptides.

Need Help?
Have questions about using this calculator or peptide therapy in general?Contact us or consult with a qualified healthcare provider experienced in peptide therapy.

Learn More About Accurate Peptide Dosing:

Peptide Calculator: The Ultimate Guide for Accurate Dosing- Comprehensive guide covering everything from basic reconstitution to advanced protocols.

Can I use regular sterile water instead of bacteriostatic water?
You can, but sterile water significantly reduces vial stability after reconstitution. With sterile water, peptides typically remain stable for only 3-5 days versus 28 days with bacteriostatic water. This means more waste and more frequent reconstitution.
What syringe size should I use?
Most peptide users rely on insulin syringes:

1ml (100 unit) syringes: Most versatile, works for most protocols

0.5ml (50 unit) syringes: Better for very small doses, offers finer gradations

0.3ml (30 unit) syringes: Best for micro-dosing protocols
How do I know if my peptides are still good?
Look for:

Clear, colorless solution (cloudiness indicates problems)

No unusual odor

Within 28 days of reconstitution

Stored properly in refrigerator

Continued therapeutic effects
Can I reconstitute half a vial?
While technically possible, it's not recommended. You'll need to estimate the powder amount, which introduces significant error. Peptides are manufactured and tested as complete vials.
What if I draw the wrong dose?
If you realize before injecting, carefully expel the solution back into the vial and redraw the correct amount. If you've already injected, don't panic—single dose variations rarely cause issues. Simply calculate and use the correct dose going forward.
Do I need to recalculate if I change peptides?
Yes, different peptides require different doses. Even if you use the same vial size and reconstitution volume, your target dose will likely differ, requiring new calculations for units to draw

Important Disclaimer:

This peptide calculator is provided for research and educational purposes only and does not constitute medical advice, diagnosis, or treatment.

Assumption of Risk: Use of this calculator and any actions you take based on its results are at your own risk. We make no warranties regarding accuracy and are not liable for any damages, injuries, or losses arising from use of this tool.

Regulatory Notice: Many peptides are for research use only and may not be FDA-approved for human use. Verify the legal status in your jurisdiction.

Individual results vary. Never disregard professional medical advice or delay seeking it because of information on this website. In case of emergency or adverse reaction, seek immediate medical attention.

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Peptide Calculator: Accurate Reconstitution & Dosage Calculations