Free hydration calculators, plain-English brand reviews, and water type guides written by people who actually drink the stuff. No marketing fluff, no paid endorsements — just useful answers.
Five calculators built around the questions our readers actually ask. No signups, no email walls, no ads in the way.
Get your personal daily water target based on weight, activity level, and climate. The "8 glasses a day" rule is too generic — this isn't.
Calculate nowWatson formula — the same one researchers use in clinical studies.
Try itQuick pH, TDS & turbidity reading — find out if you actually need a filter.
Check nowGet realistic install + running costs before any salesman quotes you.
EstimateGallons, litres, ounces, kilos — every unit you'd ever convert.
ConvertEvery type has a use case. Skip the bottled-water marketing and learn what's actually different.
Carbonated, bubbly, hydrating. Brand reviews + the science.
Mineral-free water from steam. Where it shines, where it doesn't.
5-gallon refills explained. Costs, exchanges, real numbers.
What "mineral" means on a label, and which brands deliver.
Glass vs plastic, BPA, microplastics — the bottles worth buying.
Higher pH, big claims. Where the science actually stands.
RO, UV, deionized — what's removed and what's worth it.
The internet's favorite debate, settled with proper physics.
Bold answer first, the details after. The same way we'd answer a friend.
Most adults need 2.7 to 3.7 litres (91 to 125 oz) of total water per day, including water from food. Active people, hot climates, pregnancy, fever, or stomach bugs all push that number up. The "8 glasses a day" rule is a useful floor — your real target depends on body size and activity. Use our calculator for a personal number.
Filtered tap water or spring water for most people. Both contain trace minerals (calcium, magnesium) that are mildly beneficial, and tap water in the US/UK/EU is regulated more strictly than most bottled brands. Distilled water is mineral-free — fine occasionally but not ideal as your only source. Alkaline water has no proven health benefit despite the marketing.
Plain sparkling water is mostly safe. It's mildly acidic from carbonation, but far less so than soda or juice — studies show no meaningful enamel damage from unsweetened sparkling water. Sensitive stomachs may feel mild bloating from the bubbles. Avoid flavoured sparkling waters with citric acid if you have GERD or worn enamel.
Start with your local water quality report — every US public utility publishes one annually (search "[your city] water quality report"). For wells, get tested every 1–2 years for bacteria, nitrates, and pH. Metallic taste or chlorine smell? A basic carbon filter usually fixes it. Quick checker tool here.
Roughly 50–65% in adults — men average 60%, women 55%, infants up to 78%. Higher body fat lowers the percentage because fat tissue holds less water than muscle. The number changes daily based on hydration, but normal swings aren't concerning.
Yes, if your water is above 7 grains per gallon hardness. Hard water shortens the life of dishwashers, water heaters, and faucets, and leaves skin and hair feeling rough. A whole-house softener costs $1,000–$3,500 installed and pays back in 4–7 years. Below 3 gpg? Skip it.
No sponsorships from any brand. These are real reviews — lab specs, taste tests, reader feedback.
Long-form pieces on water types, hydration science, and product comparisons. New post most weeks.
By Ryan Cooper · Reviewed by Dr. Emily Carter Published: May 2, 2026 · 8 min read You…
Read full guide
By Lauren Brooks · Reviewed by Dr. Emily Carter Published: May 2, 2026 · 9 min read ·…
Read full guide
Water is essential for life — yet most people drink far less than their body needs. From energy…
Read full guide
Water is life. Every cell, tissue, and organ in your body depends on it. Yet many people don’t…
Read full guide
Do you feel tired, dizzy, or get frequent headaches? You might not be drinking enough water. Dehydration is…
Read full guide
Have you ever heard that the full moon can affect your mood, sleep, or even your body? Since…
Read full guide
You’ve probably heard: “Drink water right after waking up,” “Never drink during meals,” or “Avoid water before bed.”…
Read full guide
Choosing between a tank and a tankless water heater can be confusing. Both systems have their advantages, and…
Read full guideWe're not selling you water. We're helping you understand it. Here's exactly how we work.
Every article carries the byline of the person who wrote it, with their qualifications visible. No anonymous AI-generated content.
We reference peer-reviewed studies, FDA, EPA, WHO. If we make a claim, you'll find a link to the source backing it.
We don't take payment from water brands for reviews. Affiliate links are clearly disclosed. Editorial decisions stay separate.
Guides are reviewed at least once a year. Each post shows when it was last updated — never republished as new.
No signup. No email. Just your weight, activity, and climate — we'll do the math.
Use the Free Calculator