Reconstituting a MOTS-c vial comes down to one number: how many units do you draw on the syringe? This calculator gives you that in one step. Enter how many milligrams are in your vial, how much bacteriostatic water you're adding, and your target dose, and it returns the exact insulin-syringe mark, the concentration you've made, and how many doses the vial holds.
MOTS-c is dosed in whole milligrams — community routines commonly use 5 to 10 mg per injection — which is a lot of peptide compared with the microgram doses of most research peptides. If you are still weighing the compound itself, start with the full MOTS-c overview guide and see where it fits among the best peptides for longevity. The practical answer is the vial size: MOTS-c is typically sold in larger vials, often 40 mg (and sometimes 10 mg), so that a whole-milligram dose still lands on a comfortable mark and a vial covers several injections. A 40 mg vial in 2 mL of water makes 20 mg/mL, where a 5 mg dose is a tidy 25 units and the vial gives 8 doses. Below the tool we walk through the math, why the bigger vial is the norm, and what real MOTS-c users mix.
Key Takeaways
- Two-step math: concentration = vial mg ÷ bac water mL, then units = (dose mg ÷ concentration) × 100 on a U-100 syringe.
- Anchor example: a 40 mg vial + 2 mL of bacteriostatic water = 20 mg/mL; a 5 mg dose = 0.25 mL = 25 units, and the vial gives 8 doses.
- Bigger vials keep the draw small. Because MOTS-c is dosed in whole milligrams, the common 40 mg vial (rather than a 10 mg one) makes a normal 5 mg dose a comfortable 25 units that fits one syringe with room to spare.
- A vial is several doses. Our usage data shows a median of about 5 doses per completed vial and a median draw near 50 units — well inside one barrel.
- The mg-vs-mcg slip is the dangerous one. MOTS-c is milligrams; reading it as micrograms is a 1,000× error.
- Research compound. Not FDA-approved, no established human dose — treat every figure as calculation context, not advice.
| You enter | Value | The calculator returns | Value |
|---|---|---|---|
| MOTS-c in vial | 40 mg | Concentration | 20 mg/mL |
| Bacteriostatic water | 2 mL | Volume to draw | 0.25 mL |
| Target dose | 5 mg | Draw to this mark | 25 units (U-100) |
| Syringe type | U-100 | Doses per vial | 8 |
How do you calculate a MOTS-c dose?
MOTS-c reconstitution is two steps: work out the vial's concentration, then convert your milligram dose into a volume you can read on the syringe. The units you draw are simply that volume on the insulin scale.
In plain arithmetic:
- Concentration (mg/mL) = vial mg ÷ bac water mL. A 40 mg vial in 2 mL is 40 ÷ 2 = 20 mg/mL.
- Volume (mL) = dose mg ÷ concentration. A 5 mg dose at 20 mg/mL is 5 ÷ 20 = 0.25 mL.
- Units = volume × 100 on a U-100 syringe (100 units = 1 mL). So 0.25 mL = 25 units.
Collapsed into the single formula the calculator runs:
units = (dose mg ÷ (vial mg ÷ bac water mL)) × 100 = dose mg × bac water mL ÷ vial mg × 100
Sanity-check our example: 5 × 2 ÷ 40 × 100 = 25 units. For doses per vial, divide the vial's milligrams by your dose: 40 mg ÷ 5 mg = 8 doses.
Our take: The thing to understand about MOTS-c is that the vial size does the heavy lifting. Because doses are whole milligrams, a small 10 mg vial would force a high concentration and leave little room — but the common 40 mg vial, mixed with 2 mL, puts a 5 mg dose at just 25 units, a quarter of the barrel. Pick the vial and water so your dose lands in the comfortable middle of the syringe, and MOTS-c is one of the easier peptides to draw.
Why does MOTS-c come in larger vials?
Because MOTS-c is dosed in whole milligrams, it's usually sold in larger vials — commonly 40 mg — so that the concentration stays high enough to keep a normal dose to a small, readable draw and give several doses per vial. Vial size is the lever that makes whole-milligram dosing practical.
Compare the two common sizes at the same dose. On a 40 mg vial in 2 mL (20 mg/mL), a 5 mg dose is 25 units and the vial yields 8 doses. On a 10 mg vial in 1 mL (10 mg/mL), the same 5 mg dose is 50 units and the vial gives just 2 doses. The bigger vial keeps the draw smaller and stretches further, which is why most logged MOTS-c reconstitutions use it. Across our tracked MOTS-c vials the median works out to about 5 doses per completed vial — a vial is a short course, not a single shot.
The practical takeaway: budget MOTS-c by the dose, and prefer the larger vial if you want a small draw and fewer reconstitutions. Dividing a vial price of roughly $45–95 by the doses it holds gives a true cost per dose near $14 in our data.
How much bacteriostatic water should you add to MOTS-c?
With MOTS-c, 2 mL on a 40 mg vial (giving 20 mg/mL) is the common choice — it keeps a 5 mg dose at a readable 25 units while leaving plenty of room on the barrel. The water sets the concentration, which sets where your dose lands on the syringe.
More water makes a more dilute vial and a larger draw for the same dose; less water makes a stronger vial and a smaller draw. Unlike a microgram peptide, you have room to choose: on a 40 mg vial a 5 mg dose is 12.5 units at 1 mL (40 mg/mL), 25 units at 2 mL (20 mg/mL), or 37.5 units at 3 mL (13.3 mg/mL) — all comfortably inside one syringe. The 2 mL mix is the popular middle. Because ProtocolPlus tracks reconstitutions, we can show the vial-strength × water-volume combinations real MOTS-c users log.
The pattern: the 40 mg vial at 2 mL (20 mg/mL) is the single most-logged setup, where a 5 mg dose is 25 units. The other common pick is a 10 mg vial at 1 mL (10 mg/mL), which keeps the smaller vial's draw to 50 units. Either way the crowd sizes the water so a normal dose sits well inside the barrel.
A worked walkthrough: choosing water on a 40 mg vial
Say you have a 40 mg vial and your dose is 5 mg. Run the candidate water volumes and watch where the draw lands:
- 1 mL → 40 mg/mL. 5 mg = 12.5 units. A small, concentrated draw.
- 2 mL → 20 mg/mL. 5 mg = 25 units. The common balance — easy to read, lots of headroom.
- 3 mL → 13.3 mg/mL. 5 mg = 37.5 units. A larger, very readable draw.
All three fit one syringe with room to spare, so the choice is about how big a mark you'd rather read. Most people land on 2 mL. If your dose is on the higher end (say 10 mg), the same 40 mg vial at 2 mL still only reaches 50 units — half the barrel.
How do you read MOTS-c units on an insulin syringe?
On a U-100 insulin syringe, 100 units = 1 mL, so a unit is a hundredth of a millilitre — the calculator converts your milligram dose into that unit mark. The "units" you read are a measure of volume, not of how much MOTS-c you're taking.
Three calibrations exist, and the calculator supports all three:
| Syringe | Full barrel | A 5 mg dose at 20 mg/mL reads as | Best for |
|---|---|---|---|
| U-100 (standard) | 100 units = 1.0 mL | 25 units | Most MOTS-c use |
| U-50 | 50 units = 0.5 mL | 25 units (half the barrel) | Smaller MOTS-c draws, finer marks |
| U-40 (older/vet) | 40 units = 1.0 mL | 25 units | Rare — double-check your barrel |
Because a typical MOTS-c draw on the common mix is around 25 units, a standard U-100 1 mL barrel reads it comfortably, and a U-50 0.5 mL barrel works too with finer spacing. Always confirm which syringe you're holding, since a unit means a different volume on each.
Where MOTS-c doses actually land
Mixed the usual way on a 40 mg vial, MOTS-c's 5–10 mg doses fall around 25–50 units — comfortably inside one U-100 syringe. A draw only climbs high if you pair a small 10 mg vial with a big dose and extra water, which the calculator flags.
Across our tracked MOTS-c reconstitutions the median draw is about 50 units, with the middle half running from roughly 25 to 75 units. The larger-vial habit is what keeps those draws in the readable middle of the barrel.
The distribution sits comfortably below the top of the barrel — a normal MOTS-c dose is half a syringe or less. If a draw does climb toward 100 units, it usually means a 10 mg vial mixed with too much water for the dose; the fix is the larger 40 mg vial or a little less water, and the calculator flags the rare case where a dose would pass one syringe.
MOTS-c reconstitution chart: units by vial and dose
This chart shows the concentration each vial makes at the common water volumes and the U-100 units to draw, so you can see where the 5–10 mg doses land. For any other setup, use the calculator.
| Setup | Concentration | 5 mg | 7.5 mg | 10 mg |
|---|---|---|---|---|
| 40 mg + 2 mL | 20 mg/mL | 25 u | 37.5 u | 50 u |
| 40 mg + 1 mL | 40 mg/mL | 12.5 u | 18.75 u | 25 u |
| 40 mg + 3 mL | 13.3 mg/mL | 37.5 u | 56 u | 75 u |
| 10 mg + 1 mL | 10 mg/mL | 50 u | 75 u | 100 u |
The 40 mg vial keeps the whole 5–10 mg range to half a barrel or less at any common water volume. The smaller 10 mg vial pushes a 10 mg dose all the way to a full 100 units, which is why people reach for the larger vial when doses run high. The most-searched single conversions, for a quick sanity check:
- 5 mg MOTS-c on a 20 mg/mL vial = 0.25 mL = 25 units; on a 10 mg/mL vial = 50 units.
- 10 mg MOTS-c on a 20 mg/mL vial = 0.5 mL = 50 units.
- 7.5 mg MOTS-c on a 20 mg/mL vial = 0.375 mL ≈ 37.5 units.
How many MOTS-c doses are in a vial, and what does each cost?
Doses per vial is vial milligrams ÷ your dose — and because MOTS-c usually comes in a 40 mg vial, a vial covers several doses. Dividing the vial price by that number gives a true cost per dose.
A 40 mg vial at a 5 mg dose yields 8 doses; a 10 mg vial at 5 mg gives 2. Across our tracked MOTS-c vials the median works out to roughly 5 doses per completed vial at about $14 per dose. Cost per dose is the figure to compare across products.
| Economics output | How it's computed | Example (40 mg vial, 5 mg dose, $70 vial) |
|---|---|---|
| Doses per vial | vial mg ÷ dose mg | 8 doses |
| Cost per dose | vial price ÷ doses per vial | $8.75 |
| Weekly cost | cost per dose × doses per week | $26.25 (3×/week) |
| Approx. monthly cost | weekly × 4.3 | ~$113 |
For a full schedule rather than a single calculation, see our MOTS-c dosing and protocol guide.
mg, mcg, units, and mL: keeping the four numbers straight
Milligrams measure the MOTS-c; millilitres and units measure the liquid you draw. The dangerous slip is reading its milligram dose as if it were micrograms, or vice versa — a 1,000× error. Keep the families separate and the math is easy.
MOTS-c is dosed in milligrams (5–10 mg), unlike microgram-dosed peptides such as BPC-157 or sermorelin, so if you switch between them, watch the unit. The same two-step math applies to any compound in our general peptide dosage calculator. 1 mg = 1,000 mcg. Here is a 5 mg dose expressed four ways on a 20 mg/mL vial, one quantity wearing four labels:
| Label | Value | What it describes |
|---|---|---|
| Dose in milligrams | 5 mg | mass of MOTS-c |
| Dose in micrograms | 5,000 mcg | mass of MOTS-c |
| Volume to draw | 0.25 mL | liquid volume |
| Units to draw (U-100) | 25 units | liquid volume on the syringe |
Why concentration is the number that actually matters
Concentration (mg/mL) is the hinge of every MOTS-c calculation — it connects the milligrams in the vial to the units on the syringe. Change it and the same dose lands on a different mark.
Concentration is an exchange rate between milligrams of MOTS-c and millilitres of liquid. A 20 mg/mL vial trades every 1 mL for 20 mg; your dose occupies a volume set by that rate, and the syringe scale turns it into a unit mark. Make the vial stronger (less water, or a 40 mg vial instead of a 10 mg one) and the same dose occupies less volume and fewer units. That's why the larger vial keeps MOTS-c's whole-milligram doses to a small, readable draw.
It's also why you can never compare unit numbers across reconstitutions. "Draw 25 units" means 5 mg on a 20 mg/mL vial but 2.5 mg on a 10 mg/mL vial — half. Every unit instruction online is valid only for that exact vial and water volume.
MOTS-c injection cadence
Many MOTS-c routines inject several times a week rather than daily, and each individual injection is what you run through the calculator — not a weekly sum. The calculator converts each per-injection dose into a unit mark.
Whether to dose every other day, three times a week, or in a short course is a protocol decision outside the calculator's scope. The tool simply takes whichever per-injection dose you choose and returns an accurate unit mark for your vial and water. For the schedule itself, see our MOTS-c dosing and protocol guide.
How to reconstitute MOTS-c, step by step
Add the bacteriostatic water slowly down the vial wall, swirl gently until clear, and never shake. The peptide is delicate, and rough mixing degrades it before your first dose.
- Calculate first. Use the tool above to set your water volume and target unit mark — on a 40 mg vial in 2 mL, a 5 mg dose is 25 units.
- Room temperature, then swab both stoppers with a fresh alcohol swab.
- Draw your measured water into a reconstitution syringe.
- Add slowly down the wall of the MOTS-c vial, onto the glass rather than the powder.
- Swirl, don't shake until the solution is completely clear.
- Inspect. Clear and particle-free, or don't use it.
- Label and refrigerate at 2–8 °C, then dose at the unit mark the calculator gave you.
Reconstitution troubleshooting
- The powder won't fully dissolve. Give it a few minutes and keep swirling gently; warmth helps. A vial that stays cloudy or shows particles shouldn't be used.
- Foam or a hard vacuum pull. Some vials are under vacuum; vent briefly with an empty needle or add the water slowly down the wall.
- A draw climbing toward 100 units. Usually a small 10 mg vial paired with a big dose and extra water. Use a 40 mg vial or a little less water to bring the draw back down.
Common MOTS-c reconstitution mistakes
- Treating a 40 mg vial like a small peptide vial. Match the water to the vial (about 2 mL for 40 mg) so the dose lands on a comfortable mark.
- Confusing mg with mcg. A 1,000× error; MOTS-c is milligrams.
- Reading "units" as milligrams. Units are a volume; always convert through the calculator.
- Copying someone else's unit count. Valid only for that person's exact concentration.
- Wrong syringe (U-40 vs U-100 mismatch), and not labeling the date.
MOTS-c vial sizes, supplies, and water
MOTS-c commonly comes in a 40 mg vial (10 mg vials also exist), and the larger size is what keeps a whole-milligram dose to a small, readable draw with several doses per vial. Pick the size and water volume that land your dose on a comfortable mark.
- 40 mg — the workhorse size; in 2 mL it's 20 mg/mL, where a 5 mg dose is 25 units and the vial gives 8 doses.
- 10 mg — smaller and fewer doses; in 1 mL it's 10 mg/mL, where a 5 mg dose is 50 units and the vial gives 2 doses.
A quick supplies checklist: the lyophilized MOTS-c vial, bacteriostatic water (sterile water with 0.9% benzyl alcohol) as the diluent, a reconstitution syringe (1–3 mL), a U-100 1 mL insulin syringe, alcohol swabs, and a marker for the date. Use bacteriostatic — not preservative-free or non-injectable — water for a multi-dose vial.
How long does reconstituted MOTS-c last?
Once mixed, MOTS-c is far less stable than the dry powder, and there's no validated shelf life — the common ~28-day refrigerated convention is a usage habit, not data. Judge by appearance, not just the calendar.
Peptides in solution degrade through hydrolysis, deamidation, oxidation, and aggregation, sped up by heat, light, and agitation, so a mixed vial belongs in the refrigerator at 2–8 °C, kept dark, and never frozen. In our usage data the median reconstituted MOTS-c vial is finished in about 23 days, in line with several injections a week. Discard any vial that turns cloudy, changes color, or shows particles. For the deeper science, see our peptide storage and stability guide.
What the evidence says about MOTS-c dosing
MOTS-c's dosing figures come from community practice, not human dose-finding trials — the published science is preclinical and mechanistic, so the milligram amounts people use are conventions, not validated human doses. We give them only so you know what to enter into the calculator.
MOTS-c is a 16-amino-acid mitochondrial-derived peptide encoded in mitochondrial DNA. It was first described as a regulator of metabolic homeostasis and insulin sensitivity, acting partly through the AMPK pathway (PubMed, 2015, Lee et al., "The Mitochondrial-Derived Peptide MOTS-c Promotes Metabolic Homeostasis", retrieved 2026-06-16), and was later shown to be exercise-induced and to influence age-dependent physical decline in animal models (Nature Communications, 2021, Reynolds et al., "MOTS-c is an exercise-induced mitochondrial-encoded regulator", retrieved 2026-06-16). Human work so far is largely on MOTS-c as an endogenous biomarker rather than an injected drug (NCBI/PMC, 2024, "Endurance exercise and serum MOTS-c in athletes", retrieved 2026-06-16). There is no approved label, no standard human dose, and no validated shelf life for reconstituted MOTS-c. Treat the common 5–10 mg figures as a community convention to calculate from if you choose to, not as evidence-based guidance.
How precise does your MOTS-c draw need to be?
Because MOTS-c draws are moderate (often 25–50 units), they're easy to measure accurately — one unit of error is a small fraction of the dose. On a 20 mg/mL vial, one U-100 unit is 0.2 mg, so rounding a 25-unit draw by a unit shifts a 5 mg dose by 0.2 mg, negligible. Getting the concentration right (so a normal dose lands on a readable mark) matters more than the last unit.
Frequently asked questions
Sources
Factual claims (peptide identity, evidence) are sourced below. Dose values in examples are illustrative, not recommendations; human MOTS-c dose-finding data does not exist (the evidence is preclinical and biomarker work). ProtocolPlus usage figures are first-party app data.
- PubMed (2015) — Lee C, et al., The Mitochondrial-Derived Peptide MOTS-c Promotes Metabolic Homeostasis and Reduces Obesity and Insulin Resistance, Cell Metabolism 21(3):443–454. https://pubmed.ncbi.nlm.nih.gov/25738459/ — retrieved 2026-06-16.
- Nature Communications (2021) — Reynolds JC, et al., MOTS-c is an exercise-induced mitochondrial-encoded regulator of age-dependent physical decline and muscle homeostasis. https://www.nature.com/articles/s41467-020-20790-0 — retrieved 2026-06-16.
- NCBI / PMC5663826 — Mitochondrial-derived peptides in metabolism (review). https://pmc.ncbi.nlm.nih.gov/articles/PMC5663826/ — retrieved 2026-06-16.
- NCBI / PMC11273660 (2024) — Endurance exercise and serum MOTS-c and humanin in athletes (human biomarker study). https://pmc.ncbi.nlm.nih.gov/articles/PMC11273660/ — retrieved 2026-06-16.
About this guide. Written by Jordan Vance, peptide and biohacking researcher (placeholder, replace before publish), and medically reviewed by Dr. Maya Ellison, MD, biochemistry (placeholder, replace before publish), for the ProtocolPlus Research Team. This calculator and article are educational and not medical advice.