The Peptide Calculator

Dose and volume at a known concentration

For a vial that is already mixed. Give the strength per millilitre and convert in either direction.

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

Per millilitre of finished solution.
Used when converting an amount into a volume.
Used when converting a volume into an amount.
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. An amount into a volume: V = dose / c. A 500 mcg amount at 2.5 mg/mL is 500 / 2500 = 0.2 mL, because 2.5 mg/mL is 2,500 mcg/mL.
  2. A volume into an amount: dose = V × c. The same 0.2 mL at 2.5 mg/mL holds 500 mcg.
  3. Mixing the mass units is where this goes wrong by a factor of a thousand in practice, so every field carries its unit and the two are converted explicitly rather than assumed to match.

Why this is a separate tool from the main calculator

The main calculator starts at the vial: a mass of solid and a volume of diluent, which is where the displacement question and the upper-bound caveat come from. This page starts one step later, from a concentration somebody already knows, which is the situation for a vial that has been mixed and labelled, or a solution that arrived ready-made.

That changes what the answer can promise. There is no displacement to be unsure about here, because the concentration was given rather than derived. What is unknown instead is whether the stated concentration is right, and no calculation can check that.

The thousand-fold error, and how the fields are arranged against it

Milligrams and micrograms differ by a factor of a thousand, and the two are used side by side in this field: vials are labelled in milligrams, amounts are usually discussed in micrograms. A field that silently accepts either and assumes one produces an answer that is out by 1,000 and looks exactly as confident as a correct one.

So every quantity on this site carries its unit as part of the input, conversions between units are exact integer ratios, and an operation on mismatched dimensions is refused rather than coerced. Entering a volume where a mass belongs returns a refusal, not a number.

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