Reconstitution calculator

Converts a dose you have already been given into units on a U-100 syringe. It does not set doses, and it has no per-compound presets.

Tool · Harm reduction

Arithmetic for people who have already decided. This converts a dose you have been given into units on a syringe. It does not tell you what dose to take, and it cannot tell you whether taking it is a good idea.

Why this page exists, stated plainly. This publication does not recommend doses and does not endorse using the compounds it grades. It also recognises that people take them anyway, and that reconstitution arithmetic is a documented source of ten-fold dosing errors — a decimal point in the wrong place is the difference between a dose and an overdose.

So this is a calculator, not a protocol. You supply the dose. It does the division.

Inputs

Peptide in vial

Bacteriostatic water

Dose you were given

— units on a U-100 insulin syringe

U-100 only. Every figure above assumes a U-100 insulin syringe, where 100 units is one millilitre. U-40 syringes exist, are sold for veterinary use, and are marked identically. The numbers on this page do not transfer to them — using a U-100 figure on a U-40 syringe delivers two and a half times the intended dose. Check the barrel before you draw.

The arithmetic, in full

There is no model here and nothing to estimate. It is four lines of division, and you can check them by hand.

concentration = peptide (mg) ÷ water (mL) → mg per mL per unit = concentration × 10 → mcg per unit (U-100) volume = dose (mcg) ÷ (concentration × 1000) → mL units to draw = dose (mcg) ÷ (concentration × 10) → U-100 units doses per vial = peptide (mcg) ÷ dose (mcg)

The only place a mistake hides is unit confusion: milligrams against micrograms, and U-100 against U-40. Both are thousand-fold and hundred-fold traps respectively, and both are why this page states its units on every line.

What this does not do

It does not set a dose
You supply the number. Nothing on this page suggests, defaults to, or endorses any particular dose, and there are deliberately no per-compound presets — a preset is a recommendation wearing a disguise.
It does not know what is in your vial
The arithmetic assumes the vial contains what the label says, at the stated quantity, and is sterile. For compounds bought outside a regulated supply chain, none of that is verified, and independent testing has repeatedly found otherwise.
It does not tell you the compound works
Most of the peptides people reconstitute are graded Preliminary or Untested in humans on this site. Correct arithmetic on an ineffective compound is still an ineffective compound.
It cannot tell you a trial dose
For the two most commonly reconstituted research peptides, BPC-157 and TB-500, no human trial has ever been published, so no trial dose exists. Every protocol circulating for them was reasoned backwards from rodents or invented outright. What the trials did use, for everything we grade, is on the trial protocols page.