Free sodium calculator

Sweat & sodium calculator

Estimate the fluid and sodium you lose in sweat, and the daily intake that replaces it.

Body weight
lb
Workout duration 60 min
Advanced settings
Workout intensity
Temperature
How salty a sweater are you?

How much sodium do you lose in sweat?

It comes down to two things: how much you sweat, and how salty your sweat is. Most people lose between 0.5 and 1.5 grams of sodium per liter of sweat, which is roughly 500 to 1,500 mg per liter, with about 900 mg per liter as a typical average. Table salt is around 40 percent sodium, so that is roughly 1.5 to 3.5 grams of salt for every liter you sweat out.

Your sweat rate does the rest of the math. A hard, hot hour can pull 1 to 2 liters out of you, so an hour of real effort often costs 1 to 2 grams of sodium (about 1,000 to 2,000 mg), and a 90-minute session usually runs higher. Heavy, salty sweaters, the ones whose shirts dry stiff and white, sit at the top of that range. Plain water puts the fluid back but not the sodium, which is why long or hot sessions can leave you cramping and flat even when you drink plenty.

The calculator above works as both a sweat rate and a sodium loss calculator: it turns your weight, the conditions, and how salty you run into your own estimate, then shows it in Saltivate servings so you know how much to put back.

Good to know

Sweat and sodium, answered

How much sodium do you lose in sweat?
Most people lose about 0.5 to 1.5 grams of sodium per liter of sweat, with roughly a gram per liter as an average. How much you lose overall depends on how long and hard you go and how hot it is. The calculator above estimates it for your own conditions.
How much sodium do you lose in sweat per hour?
At a typical sweat rate of about a liter an hour and roughly a gram of sodium per liter, most people lose around 1 gram of sodium per hour of hard exercise. Heavy or salty sweaters in the heat can lose 1.5 to 2 grams an hour or more.
How much sodium do you lose during 90 minutes of exercise?
A 90-minute session at a steady sweat rate often costs somewhere around 1 to 3 grams of sodium, depending on your size, the heat, and how salty your sweat is. Use the calculator above to get a number for your own session.
How much sodium is in a liter of sweat?
Roughly 500 to 1,500 mg of sodium per liter of sweat, with about 900 mg per liter as a typical average. Saltier sweaters land at the high end, which is why two people on the same run can lose very different amounts.
How much salt do you lose when you sweat?
Sodium is part of salt, and table salt is about 40 percent sodium, so 1 gram of sodium is about 2.5 grams of salt. A sweaty hour can mean roughly 2 to 5 grams of salt lost.
Does sodium loss change with heat and intensity?
Yes. Harder effort and hotter, more humid conditions raise both how much you sweat and, for many people, how concentrated that sweat is, so your sodium losses climb on hot, intense days.
Can I use this as a sweat rate calculator?
Yes. The weigh-in mode estimates your sweat rate from your weight before and after a session and what you drank, then turns that into the fluid and sodium you lost, so it works as both a sweat rate and a sodium loss calculator.
How much sodium should you replace after sweating?
Replace a meaningful share of what you lose, especially on long or hot sessions. A common starting point from the American College of Sports Medicine is roughly 300 to 600 mg of sodium per hour during prolonged exercise, with more for heavy or salty sweaters. The calculator shows your estimated loss in Saltivate servings, which carry 800mg of sodium each. A high-sodium routine is not right for everyone, so check with your doctor about the target that fits you.

Cost to hit your target

What a high-sodium routine costs per month

Enter your doctor's daily sodium target to see the servings and monthly cost across high-sodium brands.

mg / day

Get your target from your doctor. This tool just does the math.

Brand Sodium / serving Servings / day Cost / month
Saltivate 800mg 1 $0
LMNT 1000mg 1 $0
Vitassium 500mg 1 $0
NormaLyte 851mg 1 $0
DripDrop 330mg 1 $0
Liquid I.V. 510mg 1 $0
Cure 240mg 1 $0
Buoy 50mg 1 $0

Estimate only, from each brand's MSRP and label sodium. Set your target with your doctor; a high-sodium routine is not right for everyone.

Skip the math, just sip it

One scoop puts back 800mg sodium, 240mg potassium, and 60mg magnesium. Zero sugar, no stevia, HSA/FSA eligible.

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