During-effort fuel · electrolyte · reviewed 3 Sep 2026
Nuun Sport + Caffeine 37
The identical Nuun Sport electrolyte formula -- 300 mg sodium, 150 mg potassium, 4 g carbohydrate -- plus 40 mg of caffeine from organic green tea extract, at the same 75 cents a tablet as caffeine-free Nuun Sport.
Score breakdown
Each dimension below is scored 0 to 100 against a fixed scale, not against the rest of the catalog, so adding a product never moves this number. The overall score is the average of the dimensions this product declares data for. How the scales are set →
Comparison
6 of 14 electrolytes heldPrices per single sachet at the cheapest box size we track. Best in green, worst in red, across the gels shown.
| Measure | Nuun Nuun Sport + Caffeine | LMNT LMNT Citrus Salt | Nuun Nuun Sport | Precision Fuel & Hydration Precision Fuel & Hydration PH 1000 | Science in Sport SiS GO Hydro | 4Endurance 4Endurance Electrolytes |
|---|---|---|---|---|---|---|
| Overall scoreAn average of the various variables measured. | 37 | 75 | 37 | 36 | 44 | 50 |
| SodiumThe main electrolyte lost in sweat, and the biggest single driver of cramping and hyponatremia risk. | 300 mg | 1000 mg | 300 mg | 500 mg | 345 mg | 250 mg |
| PotassiumWorks alongside sodium in muscle and nerve function. | 150 mg | 200 mg | 150 mg | 130 mg | 65 mg | 70 mg |
| CalciumInvolved in muscle contraction; lost in far smaller amounts than sodium. | 13 mg | 0 mg | 13 mg | 20 mg | 102 mg | 10 mg |
| MagnesiumSupports muscle and nerve function; some evidence it blunts cramping. | 25 mg | 60 mg | 25 mg | 10 mg | 8.1 mg | 50 mg |
| CarbohydrateMinimal by design. This is a hydration product, not a fuel source. | 4 g | 0 g | 4 g | 3 g | 0.9 g | 0 g |
| Price per tabletWhat one tablet costs. | $0.75 | $1.50 | $0.75 | $1.20 | $0.75 | $0.27 |
| Cost per 1000mg sodiumThe only price that compares across different sodium concentrations. | $2.50 | $1.50 | $2.50 | $2.40 | $2.17 | $1.08 |
Verdict
what it does · what it costsWhat it does well
- Same electrolyte profile as Nuun Sport already in this catalog -- no formula trade-off for adding caffeine.
- 40 mg of caffeine, roughly half a cup of coffee, is a moderate dose next to gel-based options like Maurten Gel 100 Caf 100 (100 mg) or SiS Beta Fuel + Nootropics (200 mg).
- No price premium over plain Nuun Sport -- both run 75 cents a tablet.
- One of few caffeinated products in this catalog delivered as an electrolyte tablet rather than a gel or drink mix.
What it costs you
- 300 mg of sodium is on the lower end of the electrolyte-tablet field -- Precision Fuel & Hydration's PH 1500 carries 750 mg, SiS GO Hydro 345 mg.
- 4 g of carbohydrate and 15 kcal is negligible as a fuel source on its own.
- Caffeine dose is fixed at 40 mg -- no lower-dose or higher-dose version to titrate against.
- The 8-tube box was out of stock at time of review on nuunlife.com; single tubes were available.
Where to buy
Prices and links as last checked. The price next to the name above is per unit at the cheapest box size we track -- a single-unit price below may run higher.
Who this is for
the numbers, appliedThe field tells you what it is. This is who should act on it.
Worth the money if
- You already use Nuun Sport for electrolytes and want an easy way to add a moderate caffeine dose without switching products.
- You want a caffeine source lighter than a 100 mg gel, closer to half a cup of coffee.
Look elsewhere if
- You need a bigger sodium dose per unit -- look at Precision Fuel & Hydration's PH 1500 or SiS GO Hydro instead.
- You don't want caffeine late in a session and would rather keep plain Nuun Sport in rotation.