Peptide Reconstitution Calculator
Tell it the vial strength and the water going in. Back comes the concentration, the volume holding whatever quantity you ask for, and what that volume looks like on a U-100 barrel.
What you see here are concentrations and volumes. Nothing on this site is dosage, protocol or administration guidance, and no number above is one either.
What does this calculator work out?
Four numbers, and one division underneath all of them. First the concentration in milligrams per millilitre, which is how a solution is described. Then the volume holding whatever quantity you put in the third box. Then that same volume expressed in units on a U-100 barrel, because that is the scale on almost every syringe in circulation. Last, the micrograms per unit, worth a glance before anything is drawn, since a unit is as fine as the barrel goes.
Touch any input and all four results follow. None of it leaves your browser; the sums happen on the page.
What is reconstitution?
What is in the vial when it reaches you is lyophilised powder. Lyophilisation means freeze drying under vacuum, and what it leaves behind is a dry cake sitting at the bottom of the glass. Dry, the material holds for a very long time. That is why it travels in this state and why an unopened vial survives a shelf without a fridge.
Reconstitution is the step back to liquid. Water goes in through the stopper, the cake goes into solution, and what you have is a liquid of known strength. Note what did not happen: the amount of peptide stayed exactly where it was. Ten milligrams before, ten milligrams after, whether you put in 1ml or 5ml. All the water decided was how thinly those ten milligrams are spread, and that is the whole of its influence.
How is the concentration worked out?
Divide the milligrams in the vial by the millilitres you added. There is nothing more to it than that.
| Vial | Water added | Concentration | 0.1ml then holds |
|---|---|---|---|
| 10mg | 1ml | 10 mg/ml | 1mg |
| 10mg | 2ml | 5 mg/ml | 0.5mg |
| 10mg | 3ml | 3.33 mg/ml | 0.333mg |
| 10mg | 5ml | 2 mg/ml | 0.2mg |
Turn the sum around and you get the calculator's second job: dividing a quantity by the concentration tells you the volume that holds it. Using the second row, 0.5mg at 5 mg/ml comes out as 0.5 over 5, or 0.1ml.
Less water, stronger solution, less liquid overall. More water, weaker solution spread wider, and weaker solutions land on bigger, easier-to-read volumes along a barrel. Either way the contents of the vial are untouched.
What does a unit on a U-100 syringe mean?
U-100 describes the scale, not how big the syringe is. The markings run so that 100 units is 1ml, which puts a single unit at 0.01ml. A 1ml barrel runs to 100, a 0.5ml to 50, a 0.3ml to 30, and the gap between any two marks is the same on all of them. The short ones are just easier on the eye.
| Units | Millilitres | At 5 mg/ml that is | At 10 mg/ml |
|---|---|---|---|
| 5 | 0.05ml | 0.25mg | 0.5mg |
| 10 | 0.10ml | 0.5mg | 1mg |
| 20 | 0.20ml | 1mg | 2mg |
| 50 | 0.50ml | 2.5mg | 5mg |
| 100 | 1.00ml | 5mg | 10mg |
Micrograms per unit appears on the calculator because a unit is the smallest division the barrel can give you. At 10 mg/ml that unit carries 100mcg; at 2 mg/ml it carries 20mcg. Thinner solutions mean finer resolution, which is the argument for choosing your water volume on purpose rather than out of habit.
Which water goes into the vial?
Three different liquids get mentioned in this context, and swapping one for another is not a neutral choice.
| Bacteriostatic water | Water with 0.9% benzyl alcohol in it, there to suppress microbial growth. That alcohol is the reason a vial can be entered repeatedly and still last weeks instead of hours. Every figure on this page assumes it. |
|---|---|
| Sterile water | Sterile, but with nothing in it to hold growth back once the stopper has been pierced. Treat it as single entry. |
| Water for injection | Pharmacopoeial grade, still unpreserved. The single-entry limit applies exactly as it does to sterile water. |
Whichever of the three you use, the volume sum does not change. What changes is how many days the solution remains usable once you have been into it.
Every vial size we stock, at a glance
This comes straight off the live catalogue, so nothing appears here that is not genuinely in stock. Find your label strength down the side, then follow it across to the volume you plan to add.
| Vial | + 0.5ml | + 1ml | + 2ml | + 3ml | + 5ml | Sold as |
|---|---|---|---|---|---|---|
| 2mg | 4.00 | 2.00 | 1.00 | 0.67 | 0.40 | 3 compounds |
| 5mg | 10.0 | 5.00 | 2.50 | 1.67 | 1.00 | 11 compounds |
| 10mg | 20.0 | 10.0 | 5.00 | 3.33 | 2.00 | 20 compounds |
| 20mg | 40.0 | 20.0 | 10.0 | 6.67 | 4.00 | 2 compounds |
| 30mg | 60.0 | 30.0 | 15.0 | 10.0 | 6.00 | 2 compounds |
| 40mg | 80.0 | 40.0 | 20.0 | 13.3 | 8.00 | 2 compounds |
| 50mg | 100 | 50.0 | 25.0 | 16.7 | 10.0 | 5 compounds |
| 60mg | 120 | 60.0 | 30.0 | 20.0 | 12.0 | 1 compound |
| 70mg | 140 | 70.0 | 35.0 | 23.3 | 14.0 | 1 compound |
| 80mg | 160 | 80.0 | 40.0 | 26.7 | 16.0 | 1 compound |
| 100mg | 200 | 100 | 50.0 | 33.3 | 20.0 | 1 compound |
| 500mg | 1000 | 500 | 250 | 167 | 100 | 1 compound |
Every figure is mg/ml. Nothing is blank, because every row is a size you can actually buy.
How is the vial handled?
- Let it reach room temperature. A vial taken straight from a fridge or freezer goes in cold, and cold powder is slower to take up water.
- Clean both stoppers. The peptide vial and the water vial, with a fresh alcohol swab each, every time either is entered.
- Draw the volume you decided on from the water vial. The number from the calculator is this number.
- Send it down the glass. Angle the needle so the water runs down the inside wall and pools under the cake rather than landing on top of it.
- Swirl, do not shake. Rolling the vial between the fingers is enough. Foam on the surface is denatured protein, and it is visible evidence of damage.
- Give it time. Most cakes clear within a few minutes. A finished solution is transparent and free of particles.
- Label it. Writing the date and the concentration on the vial is what makes the figure retrievable a fortnight later, when the calculator is no longer open.
Cloudiness that will not clear, strands you can see, or material still sitting on the bottom after a long wait all mean it has not fully dissolved. That is an observation about what is in front of you rather than a judgement on the batch itself. For the batch, quote the number on the label and we will match a certificate of analysis to it.
How long does a reconstituted vial keep?
Dry and sealed is the state that lasts: years in a freezer near minus 20 degrees, months between 2 and 8 in a fridge, weeks at room temperature provided it stays dry and dark. Add water and an entirely different clock starts. With bacteriostatic water the working figure is around four weeks, refrigerated, standing upright, out of the light. With sterile water or water for injection there is no preservative at all, so the vial is single entry.
Never put a solution in the freezer. Ice crystals grow right through it and tear at the peptide as they go, and every freeze-thaw round takes a little more. Remember too that the purity figure describes the material at the moment it left testing, not after a month rattling around in a door shelf.
What if the format is already in solution?
Several formats skip all of this, because they never were a powder.
| Pens | Supplied filled. The concentration was set at filling and the dial on the barrel reads in the unit the pen is marked in. Refrigerate from arrival. |
|---|---|
| Nasal sprays | Supplied filled. Nothing is added and nothing is drawn up. |
| Capsules | A finished solid. There is no concentration to set. |
| Stacks, blends and kits | Powder, so the vial rows above apply. On a blend the figure describes the vial as a whole, and the component split is printed on the product page. |
Which compounds does this apply to?
Powder is how all of the compounds below arrive, and every one of them repeats this table in its own strengths on its own page, next to the price and the milligram rate.
- 5-Amino-1MQ 50mg
- AOD-9604 2mg, 5mg, 10mg
- ARA-290 10mg
- BPC-157 10mg
- BPC-157 + TB-500 10mg
- Cagrilintide 5mg, 10mg
- CJC-1295 DAC 2mg
- DSIP 5mg
- GHK-Cu 50mg, 100mg
- GLOW 50mg, 70mg
- Ipamorelin 5mg, 10mg
- Kisspeptin-10 5mg, 10mg
- KLOW 80mg
- KPV 10mg
- Methylene Blue 10mg
- MOTS-c 5mg, 10mg
- NAD+ 500mg
- PT-141 10mg
- Retatrutide 5mg, 10mg, 20mg, 30mg, 40mg
- Semaglutide 2mg, 5mg, 10mg
- Semax 5mg
- SLU-PP-332 10mg, 50mg
- SS-31 10mg, 50mg
- TB-500 10mg
- Tesamorelin 10mg
- Thymosin Alpha-1 5mg, 10mg
- Tirzepatide 5mg, 10mg, 20mg, 30mg, 40mg, 60mg
- VIP 10mg
Peptide Reconstitution Calculator questions
How much bacteriostatic water do I add to a 10mg vial?
That is your decision, since the 10mg stays 10mg whatever you pour in; the volume only sets the strength. Put in 1ml for 10 mg/ml, 2ml for 5 mg/ml, 3ml for 3.33 mg/ml, 5ml for 2 mg/ml. Enter 10 and your chosen volume above and the calculator gives you the figure plus what it reads on a U-100 barrel.
How do I convert mg to units on an insulin syringe?
On a U-100 barrel, 1ml spans 100 units, which puts a unit at 0.01ml. Take your milligrams, divide by the mg/ml, and you have millilitres; multiply that by 100 for units. Worked through at 5 mg/ml: 0.5mg comes to 0.1ml, and 0.1ml is 10 units.
Does adding more water mean less peptide?
Not at all. Whatever the label says is in the vial stays in the vial, whatever you add. Extra water simply spreads that same quantity across more liquid, dropping the concentration and leaving each unit on the barrel carrying less.
Can I use sterile water instead of bacteriostatic water?
The sums do not change at all. What changes is the 0.9% benzyl alcohol that bacteriostatic water carries: it holds microbial growth back, and it is the only reason a vial can be entered repeatedly. No preservative exists in sterile water or water for injection.
How long does a reconstituted vial last?
Mixed with bacteriostatic water and kept cold, upright and dark, four weeks is the number most people work to. Mix it with sterile water or water for injection and there is no preservative at all, so treat the vial as single entry.
Can I freeze a vial after mixing it?
Sealed powder, yes, and the freezer is exactly where anything long term belongs. A solution, no. Ice crystals tear at the peptide as they grow, and every freeze-thaw round takes a little more.
Why is my solution cloudy?
Usually the cake has not finished dissolving, which leaves haze or strands behind. Give it longer at room temperature and keep swirling gently. Foam is a different problem entirely: that comes from shaking, and it is damaged protein you can actually see.
Does the calculator tell me a dose?
It does not. All it does is convert between milligrams, millilitres and syringe units, which is arithmetic describing a solution. Every item we sell is an unlicensed research compound for laboratory research, and no dosage or protocol guidance appears anywhere on this site.
Do pens need reconstituting?
They do not. Pens turn up filled with the concentration already fixed, so there is nothing to add. Nasal sprays are the same, and capsules are a finished solid.
Where do I find the figures for one specific compound?
Look at that compound's own page. Every one repeats this table in its own strengths under a reconstitution heading, and the full list of compounds that ship as powder is linked above.