Water Intake Calculator — Free & Instant

Weight (lbs)

Activity

Nothing you enter is stored or sent anywhere.

Why water matters more in a deficit

Mild dehydration reads as hunger and fatigue — the two things most likely to break a weight-loss week. Hitting a water target is the cheapest adherence tool there is.

Ranges, not rules

Heat, medications, and some heart and kidney conditions change fluid needs — if that's you, your target is a clinician question.

Reviewed by Teresa Slater, CRNPBoard-certified nurse practitioner · a decade in cardiac care · the same clinician at every visit

Meet Teresa →

30-second check

See if the program fits you

Two questions. No email required, no commitment — just a straight answer about whether we can see you, before you give us anything.

First — where do you live?

State

We check your state first because our clinicians can only treat patients where they're licensed. Nothing you enter here is stored or sent anywhere.

Quick numbers — height & weight

Height (ft)

Height (in)

Weight (lbs)

Only used to compute your result in your browser — never sent or stored.

This is an eligibility signal, not medical advice or a guarantee of treatment. A licensed clinician makes every clinical decision after reviewing your full intake, and approval is never guaranteed.

Good questions

Asked before starting

Does coffee count?

Mostly yes — caffeinated drinks still hydrate, though water should carry the load.

Can you drink too much?

Yes, though it's uncommon. Extreme intakes — or fluid limits from a medical condition — belong with your clinician.