Electrolyte Need & Label Checker
Estimates your sodium and potassium needs during exercise or heavy sweating, then checks whether your electrolyte supplement label actually measures up.
Estimate Your Sodium & Potassium—Then Verify the Supplement Label
The Electrolyte Need & Label Checker estimates your likely sodium and potassium losses during exercise or heavy sweating, using your body weight, sweat rate, duration, and heat conditions. It then compares those targets to the sodium and potassium amounts listed on an electrolyte product label to help you judge whether the supplement is underdosed, a good match, or likely too concentrated.
From Sweat Rate to Targets, Then a Label “Match” Verdict
First, the tool estimates total sweat loss as sweat rate × duration. Using that sweat amount, it estimates a sodium target per hour and per session based on the selected heat/sweat condition, and it estimates a potassium target per hour and per session using a smaller per-liter assumption. Finally, it compares your product’s labeled sodium and potassium per serving against the estimated target, using a tolerance window to classify the label as underdosed (<80%), good match (80–120%), or overdosed (>120%).
Why Two People Can Need Different Electrolytes Than the Calculator Predicts
This calculator uses average, consumer-friendly electrolyte concentrations rather than measuring your individual sweat composition—so real needs can vary widely. Heat, acclimation, exercise intensity, training status, and whether you’re also replacing fluids/carb can all change how much sodium and potassium you actually benefit from. Treat the results as a practical label-screening tool, not a personalized medical prescription.
Common Input & Interpretation Mistakes to Avoid
Double-check consistency: if you choose “Cool” but enter an unusually high sweat rate, the tool may flag that your inputs don’t align well. If you enter a very high sweat rate with long duration, remember the output is an estimated need for that session—not a full-day plan. Also note that the calculator focuses on sodium and potassium only; it doesn’t account for medical conditions (like kidney disease or hypertension) or medications that may require electrolyte restrictions.
What Happens With Zeroes, Extremes, or Very Small Sessions
If duration is ≤0 or sweat rate is ≤0, the calculator can’t produce meaningful targets. If both labeled sodium and potassium are 0, it warns that the product isn’t meaningfully an electrolyte supplement. For short sessions (e.g., 15–30 minutes), the per-session target may be small—so a label that looks “high” per serving may still be appropriate if you plan to use less than one serving.