How much salt should I put in 1 liter of water?

January 10, 2026 •

4 min read

According to the World Health Organization, a standard oral rehydration solution contains half a teaspoon of salt per liter of water. The ideal amount of salt to add to 1 liter of water varies significantly depending on its intended use, from a simple electrolyte booster to a concentrated saline solution. Knowing the correct ratio is crucial for effectiveness and safety, as too much or too little can be counterproductive.

Quick Summary

The quantity of salt for 1 liter of water depends on the specific application, such as hydration, nasal irrigation, or gargling. Recommended amounts range from a tiny pinch for daily electrolytes to a half-teaspoon for a standard rehydration drink or up to 9 grams for medical-grade solutions. Different salt types and purposes require distinct measurements to ensure proper and safe use.

Key Points

Hydration needs vary: The amount of salt in 1 liter of water depends on the purpose, such as a subtle electrolyte boost for exercise or a specific medical solution.
ORS is a specific formula: A half-teaspoon of salt and six teaspoons of sugar in 1 liter of water makes a homemade oral rehydration solution to combat dehydration from illness.
Nasal rinses require precision: An isotonic saline solution for nasal irrigation needs a precise 0.9% concentration, equating to 9 grams of non-iodized salt per liter of sterile water.
Excess salt is dangerous: Consuming too much salt can lead to health problems, including high blood pressure and dehydration, and should be avoided.
Always use sterile water for medical uses: When making saline for nasal or medical purposes, use distilled, sterile, or previously boiled and cooled water to prevent infection.
Consult a professional for health concerns: Individuals with high blood pressure, kidney disease, or other health issues should consult a doctor before adding salt to their drinking water.

The amount of salt you should put in 1 liter of water is not a one-size-fits-all answer; it is highly dependent on the solution's intended purpose. Whether for rehydration, medical-grade saline, or a sore throat gargle, the salt-to-water ratio is critical for both effectiveness and safety. This guide breaks down the recommended measurements for various applications.

Basic Hydration and Electrolyte Replenishment

For general hydration or replenishing electrolytes after a moderate workout, a very small amount of salt is sufficient. Excessive intake is not necessary and can be harmful.

For light exercise or daily supplementation: Add a small pinch (about ⅛ to ¼ teaspoon) of salt to 1 liter of water. This adds approximately 300 to 600 milligrams of sodium, which helps with fluid absorption and retention.
During intense or prolonged exercise: If you are sweating heavily for an extended period, you may need a slightly higher concentration. Commercial sports drinks often contain around 460mg of sodium per liter. A quarter teaspoon of salt is a good starting point, but specialized powders may offer a more balanced electrolyte profile.

Oral Rehydration Solution (ORS)

A homemade ORS is a life-saving solution for replacing fluids and electrolytes lost due to diarrhea or vomiting. The World Health Organization (WHO) provides a standard recipe that is easy to follow.

WHO Standard Recipe: Combine half a teaspoon (approximately 2.5-3 grams) of salt with six teaspoons of sugar in 1 liter of clean drinking water.
Instructions:
1. Ensure the water is clean and safe to drink. If in doubt, boil it and let it cool completely.
2. Use a measured half-teaspoon and six teaspoons to ensure accuracy. Small culinary spoons are best.
3. Stir the mixture thoroughly until both the salt and sugar are completely dissolved.
4. Store in a covered container and refrigerate if not used immediately.

Saline Nasal Rinse

For nasal irrigation using a neti pot or sinus rinse bottle, the solution must be isotonic, meaning it has the same salt concentration as your body's fluids. This prevents stinging or irritation.

Standard Isotonic Saline Solution: A concentration of 0.9% is standard for medical saline. For a 1-liter batch, this means 9 grams of salt. This is roughly equivalent to 1 ½ to 2 teaspoons of table salt, but weighing is most accurate.
Instructions:
1. Use distilled, sterile, or previously boiled and cooled water. Tap water is not safe for nasal rinses.
2. Use non-iodized salt, as iodine can be irritating to nasal passages.
3. Dissolve 9 grams (approx. 2 teaspoons) of salt in 1 liter of lukewarm water.
4. Always follow the specific instructions of your nasal irrigation device.

Sore Throat Gargle

For a sore throat, a saltwater gargle can help reduce inflammation and wash away irritants. It does not need to be isotonic.

Standard Gargle Solution: Dissolve about half a teaspoon of salt in a glass (approximately 8 ounces or 240 mL) of warm water. For a full liter, this would scale up to about two teaspoons.

Comparison of Salt Ratios per Liter

The correct amount of salt to use is critical for each application. The following table provides a quick reference for comparison.


Purpose	Recommended Salt per 1 Liter Water	Notes
Light Hydration	⅛ to ¼ teaspoon (approx. 0.6-1.5g)	Use for general electrolyte support; a pinch is often enough.
Oral Rehydration Solution (ORS)	½ teaspoon (approx. 2.5-3g)	Use in combination with 6 teaspoons of sugar to treat dehydration from illness.
Saline Nasal Rinse	Approximately 2 teaspoons (9g)	Must be non-iodized salt and used with sterile water to avoid irritation.
Sore Throat Gargle	Approximately 2 teaspoons (around 10g)	Typically done in smaller quantities (e.g., ½ tsp per 8oz) with warm water.
Salt Water Flush	1 tablespoon (approx. 18-20g)	Used as a digestive cleanse and should only be done with medical guidance.

Potential Risks of Using the Wrong Amount

While salt is an essential mineral, consuming too much can have negative health consequences, especially for individuals with pre-existing conditions like high blood pressure or kidney disease. Over-concentrated saltwater can cause dehydration rather than alleviate it, as the body works to excrete the excess sodium. For general drinking, relying on plain water is often the best choice unless you are actively replacing significant sweat loss during intense exercise. Always consult a healthcare provider for medical advice, particularly before attempting a salt water cleanse or if you have health concerns.

Conclusion

There is no single correct answer for how much salt to add to 1 liter of water. The appropriate measurement depends entirely on the application. For mild electrolyte enhancement, a pinch is sufficient. For a homemade oral rehydration solution, a standard half-teaspoon is required alongside sugar. For a sterile nasal rinse, a very precise isotonic ratio is necessary. Always measure carefully and be mindful of your overall daily sodium intake, especially if you have existing health issues. Prioritizing correct ratios ensures safety and efficacy for your specific purpose.

Frequently Asked Questions

For a homemade sports drink, a general guideline is to add about ¼ teaspoon of salt to 1 liter of water. This provides around 600 milligrams of sodium to help replace what is lost through sweat during exercise.

For a standard saltwater gargle to soothe a sore throat, you should dissolve about half a teaspoon of salt in a glass (roughly 240 mL) of warm water.

The WHO standard recipe involves mixing half a teaspoon of salt and six teaspoons of sugar in 1 liter of clean, safe drinking water. Stir until fully dissolved before drinking.

It is best to use non-iodized salt for a nasal rinse, as iodine and anti-caking agents found in some table salts can irritate the nasal lining. Look for pickling or canning salt instead.

Adding too much salt to drinking water can lead to dehydration, high blood pressure, and strain on the kidneys. It can also cause an electrolyte imbalance, which is harmful to your body.

A salt water flush, used for digestive cleansing, typically uses 1 to 2 teaspoons of non-iodized salt dissolved in 1 liter of warm water. This practice should be approached with caution and ideally under medical supervision due to potential health risks.

Warm water can help salt and other ingredients dissolve more quickly and completely. For purposes like gargling, warm water is preferred for soothing effects, while nasal rinses also benefit from lukewarm water to prevent discomfort.