Peptide Vial Math

How much BAC water for 5 mg BPC-157?

Adding 2 mL to a 5 mg BPC-157 vial gives 2.5 mg/mL; on a U-100 syringe 1 unit = 0.025 mg. 5 mg + 2 mL = 2.5 mg/mL, so 250 mcg is 0.1 mL, or 10 units on a U-100 syringe.

Any volume works; it only sets the concentration. Confusing units with mL has caused FDA-documented dosing errors.

BPC-157 5 mg: water added vs concentration
Watermg/mLmg per unit250 mcg =
1 mL50.055 units
2 mL2.50.02510 units
3 mL1.670.016715 units

By Peptide Vial Math Editorial Team Reviewed by the team on (how we review) Updated Formulas unit-tested (methodology)

BPC-157 5 mg reconstitution calculator

Vial mg, water mL and amount give syringe units

mg

Total printed on the vial label.

mL

Diluent volume you add (1 mL = 100 units on a U-100 syringe).

Amount unit

The mass you want in one draw. 1 mg = 1,000 mcg.

Syringe barrel
Show U-40 and U-50 syringes

Result

10units

to draw on a U-100 syringe, 100-unit barrel

Vial: 5 mg with 2 mL diluent 5 mg +2 mL
Syringe filled to 10.0 of 100 units 0 10 20 30 40 50 60 70 80 90 100 U-100, 1 mL
Volume
0.1 mL
Concentration
2.5 mg/mL
Per unit
25 mcg
Draws per vial
20

5 mg + 2 mL = 2.5 mg/mL, so 250 mcg is 0.1 mL, or 10 units on a U-100 syringe.

Arithmetic only. Not a dosing recommendation. Check every figure against your vial label and lab protocol.

How much water for a 5 mg BPC-157 vial

The water volume is the one number you choose. It doesn't change how much BPC-157 is in the vial. It changes how many units each milligram takes up. The table compares common volumes for 250 mcg:

BPC-157 5 mg: water volume vs reading for 250 mcg
Water addedmg/mLmcg per unitUnits for 250 mcgSmallest U-100 barrel
0.5 mL 10 100 2.5 30-unit
1 mL 5 50 5 30-unit
1.5 mL 3.33 33.33 7.5 30-unit
2 mL 2.5 25 10 30-unit
2.5 mL 2 20 12.5 30-unit
3 mL 1.67 16.67 15 30-unit
4 mL 1.25 12.5 20 30-unit
5 mL 1 10 25 30-unit

Working backwards: to make 250 mcg read exactly 10 units, add 2 mL; for 20 units, add 4 mL. The BAC water calculator does this for any reading.

BPC-157 5 mg: mg → units charts

One chart per common water volume. Rows are reference increments, not suggested amounts. Amber values exceed a 100-unit (1 mL) barrel.

5 mg + 1 mL (5 mg/mL)

BPC-157 5 mg: 5 mg + 1 mL = 5 mg/mL, U-100 syringe
AmountmgVolume (mL)Syringe units
100 mcg 0.1 0.02 2
200 mcg 0.2 0.04 4
250 mcg 0.25 0.05 5
300 mcg 0.3 0.06 6
400 mcg 0.4 0.08 8
500 mcg 0.5 0.1 10
750 mcg 0.75 0.15 15
1,000 mcg 1 0.2 20

5 mg + 2 mL (2.5 mg/mL)

BPC-157 5 mg: 5 mg + 2 mL = 2.5 mg/mL, U-100 syringe
AmountmgVolume (mL)Syringe units
100 mcg 0.1 0.04 4
200 mcg 0.2 0.08 8
250 mcg 0.25 0.1 10
300 mcg 0.3 0.12 12
400 mcg 0.4 0.16 16
500 mcg 0.5 0.2 20
750 mcg 0.75 0.3 30
1,000 mcg 1 0.4 40

5 mg + 3 mL (1.67 mg/mL)

BPC-157 5 mg: 5 mg + 3 mL = 1.67 mg/mL, U-100 syringe
AmountmgVolume (mL)Syringe units
100 mcg 0.1 0.06 6
200 mcg 0.2 0.12 12
250 mcg 0.25 0.15 15
300 mcg 0.3 0.18 18
400 mcg 0.4 0.24 24
500 mcg 0.5 0.3 30
750 mcg 0.75 0.45 45
1,000 mcg 1 0.6 60
Engraving showing a black-and-white card held behind a burette so the curved liquid surface can be read against the scale
Reading a liquid level against a scale, 1895. On a syringe, read the stopper's leading edge. Public domain.

How much one draw can hold

A barrel's capacity caps the largest amount you can measure in one draw. The cap depends on concentration:

BPC-157 5 mg: maximum mg per full barrel
Water30 units (0.3 mL)50 units (0.5 mL)100 units (1 mL)
1 mL1.5 mg2.5 mg5 mg
1.5 mL1 mg1.67 mg3.33 mg
2 mL0.75 mg1.25 mg2.5 mg
2.5 mL0.6 mg1 mg2 mg
3 mL0.5 mg0.833 mg1.67 mg

Draws per 5 mg vial

Whole draws of each reference amount the vial contains, regardless of water volume (the water changes the reading, not the total):

BPC-157 5 mg: whole draws per vial
Amount per drawWhole drawsLeft over
100 mcg500 mg
200 mcg250 mg
250 mcg200 mg
300 mcg160.2 mg
400 mcg120.2 mg
500 mcg100 mg
750 mcg60.5 mg
1,000 mcg50 mg

Real-world yield is usually lower: some liquid stays in the vial and in the syringe's dead space.

Other BPC-157 vial sizes

Or go back to the main BPC-157 calculator, which compares every size side by side.

Frequently asked questions

How much bacteriostatic water do I add to a 5 mg BPC-157 vial?

Any volume works mathematically; the choice sets the concentration. 1 mL gives 5 mg/mL (50 mcg per U-100 unit); 2 mL gives 2.5 mg/mL (25 mcg per U-100 unit); 3 mL gives 1.67 mg/mL (16.67 mcg per U-100 unit). 2 mL is a common choice because it keeps the arithmetic round.

How many units is 250 mcg from a 5 mg BPC-157 vial?

With 1 mL: 5 units. With 2 mL: 10 units. With 3 mL: 15 units. The amount of BPC-157 is the same in every case; only the volume it is dissolved in changes.

How many mg of BPC-157 is 10 units from a 5 mg vial?

10 units on a U-100 syringe is 0.1 mL. With 1 mL of water that is 0.5 mg; With 2 mL of water that is 0.25 mg; With 3 mL of water that is 0.167 mg.

How much BPC-157 fits in one syringe from a 5 mg vial?

At 2.5 mg/mL (2 mL of water), a 30-unit barrel holds up to 0.75 mg, a 50-unit barrel 1.25 mg and a 100-unit barrel 2.5 mg per draw.

Is this a dosing chart?

No. These are arithmetic tables for converting an amount into a syringe reading for a given vial. They do not recommend any amount or schedule.

Storing the BPC-157 vial after mixing

Reconstitution changes how a vial has to be kept: a lyophilized powder and a solution have different temperature, light and time limits, and an opened multi-dose diluent vial has its own clock (CDC guidance: discard 28 days after first puncture unless the manufacturer gives another date). The peptide storage guide covers both states, and the bacteriostatic water guide covers the diluent. Label each vial with the amount, the water added, the concentration and the date.

Sources

  1. FDA alerts health care providers, compounders and patients of dosing errors associated with compounded injectable semaglutide products — U.S. Food and Drug Administration, 2024

Links checked 2026-10-19.