The Peptide Calculator

Blended vial calculator

Two solids, one diluent volume. Each has its own concentration in the same solution, and one draw carries both in a fixed ratio.

Educational arithmetic only. Not medical advice and not a dosing protocol.

Solving for one component fixes the other, and both are reported.
No default: the same volume reads differently on each.

Fill in the fields above to see the answer.

Read this with the answer

This is educational arithmetic on figures entered by the reader. It is not medical advice, not a dosing protocol, and not a recommendation that anything be prepared, obtained or administered.

Nothing here states what quantity is appropriate for anyone, and there is no function in it that produces an amount to administer. A question about anyone’s health belongs with a licensed clinician who can examine the person asking.

Most compounds named here are research chemicals that are not approved by the FDA for human use. An exact calculation is not an accurate measurement: what is actually in a syringe depends on the preparation and the device, neither of which this page can see.

No qualified clinical reviewer is recorded against this site, and no credential is claimed anywhere on it. Full disclaimer.

Show the working
  1. Each component is concentrated against the WHOLE solution volume, not against a share of it: 10 mg of each compound in 2 mL is 5 mg/mL of each, not 5 mg/mL of the pair.
  2. The total solid in the vial is the sum of the components, and it is the total that displaces volume, so the upper-bound caveat applies more strongly here than to a single compound.
  3. Because the volume is shared, the ratio in any draw is fixed by the masses in the vial. Solving the volume from a target amount of one component determines the amount of every other component in that same volume, and those amounts are listed with it.

The error this page exists to prevent

A blended vial is not two vials. There is one solution and one volume, so a drawn volume carries every component at once, in the proportion set when the vial was filled. Nobody drawing from a blend gets to choose one component's amount on its own.

A calculator that lets a reader solve for one component and then shows only that component has concealed half of what is in the syringe. So this one always reports both: enter a target for the first compound and the answer states the volume, the amount of the first compound in it, and the amount of the second that necessarily comes with it.

The ratio is a property of the vial

A vial filled with 10 mg of one compound and 20 mg of another is a 1:2 blend at every volume drawn from it, and no arithmetic downstream changes that. Changing the ratio means filling a different vial, not drawing differently from this one.

The practical consequence is that a blend removes a degree of freedom. Two separate vials can be drawn independently; one blended vial cannot. That is a fact about the preparation, and it is the reason the ratio is printed alongside the concentrations.

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