Reconstituting an NAD+ 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.
NAD+ stands out from most injectables because everything about it is bigger: it's dosed in tens of milligrams (commonly 50–100 mg), so it ships in large vials — typically 500 mg or 1000 mg — that you reconstitute with a matching amount of water (5–10 mL). Mixed that way, a vial sits at around 100 mg/mL, where a normal dose lands on a comfortable mid-barrel mark and a single 500–1000 mg vial holds a couple of weeks of doses. The other thing to plan around is that NAD+ stings going in, which is its own reason to think about concentration. Below the tool we walk through the math, why bigger vials keep the draw sensible, the stinging, and what real NAD+ users mix. For the wider context on why people run it, see our roundup of the best peptides for longevity.
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 500 mg vial + 5 mL of bacteriostatic water = 100 mg/mL; a 50 mg dose = 0.5 mL = 50 units, and the vial gives 10 doses.
- Match the water to the vial. Big vials take more water: 500 mg in 5 mL or 1000 mg in 10 mL both make 100 mg/mL, so a 50 mg dose is 50 units and a 100 mg dose is a full-but-fits 100 units.
- A vial is many doses. At ~50 mg, a 500 mg vial holds about 10 doses, and our median works out near 10 doses per vial — NAD+ is dosed big but bought in bulk.
- NAD+ stings. A more dilute, slowly injected dose is gentler; some people also split a dose across two sites purely for comfort, not because it won't fit.
- Not an approved injectable. Robust evidence is for oral precursors; treat injectable figures as calculation context, not advice.
| You enter | Value | The calculator returns | Value |
|---|---|---|---|
| NAD+ in vial | 500 mg | Concentration | 100 mg/mL |
| Bacteriostatic water | 5 mL | Volume to draw | 0.5 mL |
| Target dose | 50 mg | Draw to this mark | 50 units (U-100) |
| Syringe type | U-100 | Doses per vial | 10 |
How do you calculate an NAD+ dose?
NAD+ reconstitution is two steps: work out the vial's concentration, then convert your milligram dose into a volume you can read on the syringe. Because NAD+ vials are large and you mix them with a matching amount of water, that volume lands comfortably inside one barrel.
In plain arithmetic:
- Concentration (mg/mL) = vial mg ÷ bac water mL. A 500 mg vial in 5 mL is 500 ÷ 5 = 100 mg/mL.
- Volume (mL) = dose mg ÷ concentration. A 50 mg dose at 100 mg/mL is 50 ÷ 100 = 0.5 mL.
- Units = volume × 100 on a U-100 syringe (100 units = 1 mL). So 0.5 mL = 50 units — half the barrel.
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: 50 × 5 ÷ 500 × 100 = 50 units. For doses per vial, divide the vial's milligrams by your dose: 500 mg ÷ 50 mg = 10 doses.
Our take: The trick with NAD+ is to match the water to the vial. People who run into trouble usually grabbed a small-vial habit — 2 mL, like a peptide — and poured it into a 500 mg vial, ending up with an absurdly concentrated, stinging mix. Reconstitute a big vial with a big volume (500 mg in 5 mL, 1000 mg in 10 mL) and you land at a clean 100 mg/mL, where the whole 50–100 mg dose range fits one syringe and the injection is far more tolerable.
How much bacteriostatic water should you add to NAD+?
With NAD+, scale the water to the vial so you land near 100 mg/mL — about 5 mL for a 500 mg vial, 10 mL for a 1000 mg vial — which keeps a normal dose on a readable mid-barrel mark and makes the injection gentler. The water choice is mostly about concentration and comfort, not about fitting the dose.
At 100 mg/mL, a 50 mg dose is 50 units and a 100 mg dose is 100 units — both inside a single U-100 barrel. Going more concentrated than that (less water) shrinks the draw further but stings more; going much more dilute makes the injection gentler but eventually pushes a big dose toward the top of the barrel. The sweet spot most people settle on is right around 100 mg/mL, which is exactly why the large vials pair with large water volumes. Because ProtocolPlus tracks reconstitutions, we can show the vial-strength × water-volume combinations real NAD+ users log.
The pattern: users converge on roughly 100 mg/mL, whether from a 500 mg vial in 5 mL (the single most-logged setup) or a 1000 mg vial in 10 mL. The 1000 mg vial in 5 mL (200 mg/mL) is the other common choice for those who want the smallest possible draw and don't mind a sharper sting. Almost nobody under-fills a big vial, because that produces a stinging, syrupy concentrate.
A worked walkthrough: water choice for NAD+
Say you have a 500 mg vial and your dose is 50 mg. Run the candidate water volumes and weigh draw size against stinging:
- 2.5 mL → 200 mg/mL. 50 mg = 25 units. A small, concentrated draw that stings more.
- 5 mL → 100 mg/mL. 50 mg = 50 units. The common balance — comfortable mark, tolerable injection.
- 10 mL → 50 mg/mL. 50 mg = 100 units. The gentlest injection, though now a 100 mg dose would fill the whole barrel.
Unlike a tiny-dose peptide, NAD+ gives you room to choose for comfort: more water means a gentler injection and a larger, easy-to-read mark, with the only limit being the size of the barrel. The 5 mL mix (100 mg/mL) is the popular middle.
Switching vials: always recalculate
Moving to a different vial strength or water volume changes the concentration, so the same dose draws to a different mark. A 50 mg dose is 50 units on a 100 mg/mL vial (500 mg in 5 mL) but 25 units on a 200 mg/mL vial (1000 mg in 5 mL). Never carry a unit number across vials — re-run the calculator every time the vial strength or water volume changes.
How precise does your NAD+ draw need to be?
Because NAD+ draws are moderate to large (often 50–100 units), they're easy to measure accurately — a unit or two of error is a tiny fraction of the dose. On a 100 mg/mL vial, one U-100 unit is 1 mg, negligible against a 50 mg dose. Precision is rarely the concern with NAD+; getting the concentration right (so the injection is tolerable) matters more.
How do you read NAD+ 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. At a sensible ~100 mg/mL mix, a normal NAD+ dose lands between about a quarter and a full barrel.
NAD+ doses are large enough that you'll almost always use a U-100 1 mL syringe (the biggest standard insulin barrel); a smaller U-50 (0.5 mL) can only hold doses up to about 50 mg at 100 mg/mL. The U-40 calibration exists but is rare; on it, the same volume reads as fewer units, so always confirm your barrel. The reconstitution syringe you use to add the water is separate and larger — for a 1000 mg vial you'll be drawing 10 mL of bacteriostatic water, which needs a 10 mL syringe.
Where NAD+ doses actually land on the syringe
Mixed the usual way at about 100 mg/mL, NAD+'s 50–100 mg doses fall between roughly 50 and 100 units — comfortably inside one U-100 syringe. A dose only approaches or passes the top of the barrel if the vial is mixed unusually dilute.
Across our tracked NAD+ reconstitutions the median draw is about 50 units, with the middle half running from 50 up to a full 100. The big-vial, big-water habit is what keeps those draws sensible: people size the water so a normal dose reads cleanly on one syringe.
The distribution sits in the usable middle-to-upper half of the barrel: a typical 50 mg dose is half a syringe, and a larger 100 mg dose fills it. A draw only exceeds one syringe if you've mixed the vial more dilute than usual (for example a 100 mg dose at 50 mg/mL), which the calculator still flags — but with the standard ~100 mg/mL mix it simply doesn't come up.
Should you split an NAD+ dose?
You usually don't have to split an NAD+ dose to make it fit — at a normal ~100 mg/mL mix a 50–100 mg dose is one syringe — but some people deliberately split a dose across two sites to ease the stinging. Splitting is a comfort choice for NAD+, not a requirement.
Because NAD+ can burn going in, a larger dose injected all in one spot can be uncomfortable. Spreading, say, a 100 mg dose across two 50-unit injections in different sites makes each one gentler and lets you go slower, which NAD+ rewards. That's optional. The only time splitting becomes a fitting issue is if you've mixed the vial unusually dilute so a single dose runs past 100 units — in which case the cleaner fix is to re-mix nearer 100 mg/mL. How a full protocol ramps the dose week to week is covered in the linked guide; the calculator's job is to convert each dose into a unit mark and flag the rare case where one won't fit.
Why does NAD+ sting, and what helps?
Subcutaneous NAD+ commonly causes a burning or stinging sensation during injection — injecting slowly and not over-concentrating the vial are the usual mitigations. It's a tolerability quirk worth planning your concentration around.
Many users report that NAD+ stings or burns under the skin, more than a typical peptide. The common practical responses are to inject slowly (over many seconds), avoid an over-concentrated mix (sticking near 100 mg/mL rather than going stronger), let the solution reach room temperature, and rotate or split across injection sites. This is why the water volume isn't just arithmetic for NAD+: the same mix that lands your dose on a clean mark also sets how sharp the injection feels. None of this is medical advice; it's the community-reported handling, and tolerability varies.
How many NAD+ doses are in a vial, and what does each cost?
Doses per vial is vial milligrams ÷ your dose — and because NAD+ comes in large 500–1000 mg vials, a single vial holds roughly one to two weeks of doses. Dividing the vial price by that number gives a true cost per dose.
A 500 mg vial at a 50 mg dose yields 10 doses; a 1000 mg vial at 100 mg gives 10 as well. Across our tracked NAD+ vials the median works out to roughly 10 doses per completed vial at about $11 per dose. Cost per dose is the figure to compare across products.
| Economics output | How it's computed | Example (500 mg vial, 50 mg dose, $110 vial) |
|---|---|---|
| Doses per vial | vial mg ÷ dose mg | 10 doses |
| Cost per dose | vial price ÷ doses per vial | $11.00 |
| Approx. weekly cost | cost per dose × doses per week | $22.00 (2×/week) |
| Approx. monthly cost | weekly × 4.3 | ~$95 |
For a full ramp-up plan rather than a single calculation, see our NAD+ dosing and protocol guide.
NAD+ 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 for typical doses, so you can pick a setup that keeps your dose on a comfortable mark. For any other setup, use the calculator.
| Setup | Concentration | 25 mg | 50 mg | 100 mg |
|---|---|---|---|---|
| 500 mg + 5 mL | 100 mg/mL | 25 u | 50 u | 100 u |
| 1000 mg + 10 mL | 100 mg/mL | 25 u | 50 u | 100 u |
| 1000 mg + 5 mL | 200 mg/mL | 12.5 u | 25 u | 50 u |
| 500 mg + 10 mL | 50 mg/mL | 50 u | 100 u | 200 u — re-mix stronger |
The cleanest, most common setups are the 100 mg/mL mixes (500 mg + 5 mL or 1000 mg + 10 mL), where the whole 25–100 mg range fits one syringe. The only row that overflows is the unusually dilute 500 mg + 10 mL with a big dose — easily avoided by mixing nearer 100 mg/mL. The most-searched single conversions, for a quick sanity check:
- 25 mg NAD+ on a 100 mg/mL vial = 0.25 mL = 25 units.
- 50 mg NAD+ on a 100 mg/mL vial = 0.5 mL = 50 units.
- 100 mg NAD+ on a 100 mg/mL vial = 1.0 mL = 100 units (a full syringe, still one draw).
Why concentration is the number that actually matters
Concentration (mg/mL) is the hinge of every NAD+ calculation — and for NAD+ it sets both the unit mark and how much the injection stings. It connects the milligrams in the vial to the units on the syringe.
Concentration is an exchange rate between milligrams of NAD+ and millilitres of liquid. A 100 mg/mL vial trades every 1 mL for 100 mg; your dose occupies a volume set by that rate, and the syringe scale turns it into a unit mark. Mix a big vial with a matching big volume of water and you land near 100 mg/mL, where doses read cleanly and the injection is tolerable; under-fill it and you get a small but sharply stinging draw. That link between concentration and comfort is what makes the water choice matter for NAD+ beyond the arithmetic.
It's also why you can never compare unit numbers across reconstitutions. "Draw 50 units" means 50 mg on a 100 mg/mL vial but 100 mg on a 200 mg/mL vial — double. Every unit instruction online is valid only for that exact vial and water volume.
mg, mcg, units, and mL: keeping the numbers straight
Milligrams measure the NAD+; millilitres and units measure the liquid you draw. NAD+ is dosed in large milligram amounts, so the trap isn't a mg/mcg mix-up — it's matching the water volume to a big vial. The same reconstitution logic underpins our general peptide dosage calculator. Here is a 50 mg dose expressed four ways on a 100 mg/mL vial:
| Label | Value | What it describes |
|---|---|---|
| Dose in milligrams | 50 mg | mass of NAD+ |
| Volume to draw | 0.5 mL | liquid volume |
| Units to draw (U-100) | 50 units | liquid volume on the syringe |
| Share of one barrel | half | how much of the syringe |
How to reconstitute NAD+, step by step
Add the bacteriostatic water slowly down the vial wall, swirl gently until clear, and never shake. NAD+ powder can be bulky in a large vial; give it time to dissolve.
- Calculate first. Use the tool above to set your water volume and target unit mark — aim for about 100 mg/mL so a normal dose fits one syringe.
- Room temperature, then swab both stoppers with a fresh alcohol swab.
- Draw your measured water into a reconstitution syringe — for a 500 mg vial that's about 5 mL, for a 1000 mg vial about 10 mL.
- Add slowly down the wall of the NAD+ 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, injecting slowly to reduce stinging.
Common NAD+ reconstitution mistakes
- Under-filling a big vial. Pouring 2 mL into a 500 mg vial makes a 250 mg/mL concentrate that stings hard — match the water to the vial (about 5 mL) for ~100 mg/mL.
- Over-diluting. Going far past 100 mg/mL can push a big dose toward the top of the barrel; stay near 100 mg/mL.
- Injecting too fast. This worsens the sting; go slow.
- Reading "units" as milligrams, wrong syringe scale (U-40 vs U-100), and not labeling the date.
NAD+ vial sizes, supplies, and water
NAD+ vials commonly come in 500 mg and 1000 mg (100 and 250 mg also exist), and you reconstitute them with a matching amount of water — about 5 mL and 10 mL respectively — to land near 100 mg/mL. Pick the size that suits how long you want a vial to last.
- 500 mg — the most-logged size; in 5 mL it's 100 mg/mL, where a 50 mg dose is a comfortable 50 units and the vial gives about 10 doses.
- 1000 mg — fewer reconstitutions, more doses; in 10 mL it's also 100 mg/mL, or in 5 mL a stronger 200 mg/mL for the smallest draws.
A quick supplies checklist: the lyophilized NAD+ vial, bacteriostatic water (sterile water with 0.9% benzyl alcohol) as the diluent, a larger reconstitution syringe (5–10 mL, since you're adding a lot of water), a U-100 1 mL insulin syringe for the dose, alcohol swabs, and a marker for the date. Use bacteriostatic — not preservative-free or non-injectable — water for a multi-dose vial.
NAD+ injection vs IV and oral NMN/NR
This calculator is for subcutaneous NAD+ injection; IV NAD+ is administered differently in a clinical setting, and oral NMN/NR are entirely different products with their own doses. Knowing which you have tells you whether this math applies.
Subcutaneous NAD+ — the reconstituted vial this page is about — is self-injected in the tens of milligrams. IV NAD+ is infused over hours at much higher totals under supervision, with no syringe-unit math for you to do. Oral NMN and NR are NAD+ precursors taken as capsules or powder, dosed in hundreds of milligrams by mouth, with no reconstitution. They are not interchangeable with injectable NAD+. For the routes compared, see our NAD+ IV vs subcutaneous vs oral guide.
How long does reconstituted NAD+ last?
Once mixed, NAD+ is less stable than the dry powder, and there's no validated injectable shelf life — the common ~28-day refrigerated convention is a usage habit, not data. Judge by appearance.
Keep a mixed vial in the refrigerator at 2–8 °C, dark, and never frozen; discard it if it turns cloudy, discolors, or shows particles. In our usage data the median reconstituted NAD+ vial is finished in about 27 days, which fits the one-to-two-week-per-vial dosing math. For the deeper science, see our peptide storage and stability guide.
What the evidence says about NAD+ dosing
The strongest human NAD+ evidence is for oral precursors (NMN and NR), which reliably raise blood NAD+ but show inconsistent clinical outcomes; rigorous trial data on injectable subcutaneous NAD+ specifically is lacking — so injectable dose figures are clinic and community conventions, not validated. We give them only so you know what to enter.
Reviews of NAD+-boosting supplementation in humans emphasize that raising blood NAD+ does not reliably translate to raised tissue NAD+ or clear clinical benefit (NCBI/PMC, 2023, "Dietary Supplementation With NAD+-Boosting Compounds in Humans", retrieved 2026-06-16). Controlled trials of oral nicotinamide riboside show it is well tolerated and elevates NAD+ (Martens et al., 2018, Nature Communications, retrieved 2026-06-16), while meta-analyses of oral NMN find raised NAD+ but mostly non-significant clinical endpoints versus control (PubMed, 2024, NMN systematic review and meta-analysis, retrieved 2026-06-16). None of this is dose-finding evidence for injectable NAD+, which has no approved label or standard dose. Treat the common 50–100 mg figures as a community/clinic convention to calculate from if you choose to, not as evidence-based guidance.
Frequently asked questions
Sources
Factual claims (evidence, status) are sourced below. Dose values in examples are illustrative, not recommendations; injectable NAD+ dosing is a community/clinic convention, not validated. ProtocolPlus usage figures are first-party app data.
- NCBI / PMC (2023) — Dietary Supplementation With NAD+-Boosting Compounds in Humans: Current Knowledge and Future Directions. https://pmc.ncbi.nlm.nih.gov/articles/PMC10692436/ — retrieved 2026-06-16.
- Martens et al. (2018), Nature Communications — Chronic nicotinamide riboside supplementation is well-tolerated and elevates NAD+ in healthy middle-aged and older adults. https://www.nature.com/articles/s41467-018-03421-7 — retrieved 2026-06-16.
- PubMed (2024) — Efficacy of oral NMN supplementation: a systematic review with meta-analysis of randomized controlled trials. https://pubmed.ncbi.nlm.nih.gov/39116016/ — 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.