During-effort fuel · electrolyte · reviewed 28 Aug 2026
GU Hydration Drink Tabs 35
320 mg of sodium per tablet is 70 mg more than Precision's PH 500 (250 mg) but less than half of PH 1500's 750 mg, paired with 55 mg of potassium and just 3 g of carbs, built for topping off electrolytes without adding real fuel.
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
5 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 | GU Energy Labs GU Hydration Drink Tabs | LMNT LMNT Citrus Salt | Nuun Nuun Sport | Precision Fuel & Hydration Precision Fuel & Hydration PH 1000 | Science in Sport SiS GO Hydro |
|
|---|---|---|---|---|---|---|
| Overall scoreAn average of the various variables measured. | 35 | 75 | 37 | 36 | 44 | |
| SodiumThe main electrolyte lost in sweat, and the biggest single driver of cramping and hyponatremia risk. | 320 mg | 1000 mg | 300 mg | 500 mg | 345 mg | |
| PotassiumWorks alongside sodium in muscle and nerve function. | 55 mg | 200 mg | 150 mg | 130 mg | 65 mg | |
| CalciumInvolved in muscle contraction; lost in far smaller amounts than sodium. | not declared | 0 mg | 13 mg | 20 mg | 102 mg | |
| MagnesiumSupports muscle and nerve function; some evidence it blunts cramping. | not declared | 60 mg | 25 mg | 10 mg | 8.1 mg | |
| CarbohydrateMinimal by design. This is a hydration product, not a fuel source. | 3 g | 0 g | 4 g | 3 g | 0.9 g | |
| Price per tabletWhat one tablet costs. | $0.67 | $1.50 | $0.75 | $1.20 | $0.75 | |
| Cost per 1000mg sodiumThe only price that compares across different sodium concentrations. | $2.09 | $1.50 | $2.50 | $2.40 | $2.17 |
Verdict
what it does · what it costsWhat it does well
- 320 mg sodium and 55 mg potassium per tablet for just 10 calories and 3 g of carbs
- 67 cents a tablet in a 12-count tube, cheaper per serving than Skratch's $1.20 scoop or Precision's 80 cents-$1.20 tablets
- Sweetened with stevia and cane sugar rather than the sucralose used in Precision's PH tablets
What it costs you
- Calcium and magnesium aren't declared on the label; only sodium and potassium are broken out
- 3 g of carbs and 1 g of sugar won't offset a bonk the way a 19 g-carb drink mix like Skratch's will
- GU's own site sells only in boxes of 4 or 8 tubes (48-96 tablets); no single-tube trial size direct from the brand
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 want a low-cost, low-calorie tablet for all-day sipping rather than a carb-carrying sports drink
- You're comparing tablet electrolytes and want a middle dose between Precision's PH 500 and PH 1500
Look elsewhere if
- You need calcium or magnesium numbers for a documented electrolyte plan; GU doesn't disclose them
- You want carbohydrate alongside electrolytes; GU's 3 g per tablet is negligible next to a drink mix