How many units is 2 mg of TB-500?

It depends entirely on how much water you added. In a 5 mg vial reconstituted with 2 mL, the concentration is 2.5 mg/mL, so 2 mg is 0.8 mL, which is 80 units on a U-100 insulin syringe. In the same vial with 1 mL of water it is 40 units, and with 3 mL it is 120 units.

How much bacteriostatic water for a 5 mg TB-500 vial?

2 mL is the usual choice. It gives 2.5 mg/mL, which puts the commonly reported range of 0.5 mg to 10 mg between roughly 20 and 400 units. Aim for a draw between about 10 and 50 units, where the barrel is easiest to read, and add or remove water to get there.

How many doses are in a 5 mg vial?

Divide 5 by your dose. At 2 mg that is 2 doses, which at twice weekly is 7 days.

How many units is 2.5 mg of TB-500?

In a 5 mg vial with 2 mL of water, 100 units, a full syringe. With 1 mL of water, 50 units.

TB-500 dosage calculator

TB-500 is dosed in whole milligrams, usually twice a week, with a higher loading phase first. Enter your vial, water and dose to get the mark.

IndependentThis site does not sell peptides and is not owned by a vendor. Every other calculator on page one of Google belongs to a shop.

The maths is openThe formula is written out on this page and the code behind it is a single file with an automated test suite.

How it earnsAffiliate links on one clearly marked page, and nowhere else. Never inside the calculator.

ReviewedDose ranges and half-life figures last checked 3 September 2026.

Dose to units, at the standard setup

Dose	Draw	U-100 units	Doses per vial	Vial lasts
1 mg	0.4 mL	40 units	5	18 days
2 mg	0.8 mL	80 units	2	7 days
2.5 mg	1 mL	100 units	2	7 days
5 mg	2 mL	200 units	1	4 days
7.5 mg	3 mL	300 units	needs a bigger vial	-
10 mg	4 mL	400 units	needs a bigger vial	-

Based on a 5 mg vial reconstituted with 2 mL of bacteriostatic water, which is 2.5 mg/mL, drawn on a standard U-100 insulin syringe, twice weekly.

About the numbers above

TB-500 is a synthetic fragment of thymosin beta-4, a protein involved in cell migration and tissue repair. It is not an approved medicine and is sold for research use.

Reported protocols usually have two phases: a loading phase of roughly 4 to 10 mg per week split into two injections for four to six weeks, then a lower maintenance dose. A 5 mg vial with 2 mL of water is 2.5 mg/mL, so 2 mg is 0.8 mL, or 80 units. Doses of 5 mg from a 5 mg vial are the whole vial. Because the draws are large, use 1 mL syringes here, and if the calculator warns the draw exceeds the syringe, use less water or split the injection.

A 5 mg vial at different water volumes

If the draw feels awkward to read, change the water rather than the dose. The dose stays the same; only the mark moves.

Vial	BAC water	Concentration	Draw	U-100 units	Doses/vial
5 mg	1 mL	5 mg/mL	0.4 mL	40 units	2
5 mg	2 mL	2.5 mg/mL	0.8 mL	80 units	2
5 mg	3 mL	1.67 mg/mL	1.2 mL	120 units	2
10 mg	1 mL	10 mg/mL	0.2 mL	20 units	5
10 mg	2 mL	5 mg/mL	0.4 mL	40 units	5
10 mg	3 mL	3.33 mg/mL	0.6 mL	60 units	5

All rows above assume a 2 mg dose and a standard U-100 insulin syringe, where 100 units = 1 mL.

How long it stays in you

Not well characterised in humans. This site only draws a decay curve where a half-life is actually documented in humans, so there is none here. Treat any precise figure you see elsewhere for TB-500 with suspicion.

Common questions

How many units is 2 mg of TB-500?: It depends entirely on how much water you added. In a 5 mg vial reconstituted with 2 mL, the concentration is 2.5 mg/mL, so 2 mg is 0.8 mL, which is 80 units on a U-100 insulin syringe. In the same vial with 1 mL of water it is 40 units, and with 3 mL it is 120 units.
How much bacteriostatic water for a 5 mg TB-500 vial?: 2 mL is the usual choice. It gives 2.5 mg/mL, which puts the commonly reported range of 0.5 mg to 10 mg between roughly 20 and 400 units. Aim for a draw between about 10 and 50 units, where the barrel is easiest to read, and add or remove water to get there.
How many doses are in a 5 mg vial?: Divide 5 by your dose. At 2 mg that is 2 doses, which at twice weekly is 7 days.
How many units is 2.5 mg of TB-500?: In a 5 mg vial with 2 mL of water, 100 units, a full syringe. With 1 mL of water, 50 units.

Buying TB-500? The where to buy page lists the vendors this site uses and what to check before ordering, and Peptide Bureau keeps the ranked vendor scorecard.

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Read this before you use the numbers. This is a unit-conversion tool. It converts a vial strength and a volume of bacteriostatic water into a concentration, a draw volume and a mark on an insulin syringe. It does not tell you what to take, whether to take it, or whether a compound is safe for you. Most of the compounds listed here are sold for laboratory research use and are not approved for human use. Nothing on this site is medical advice. Dosing decisions belong with a licensed clinician who knows your history. Always confirm the strength printed on your own vial rather than trusting a preset.