Hydration, calibrated

Find your water line
for today.

Enter your weight, height, age, and sport. Tidemark reads your numbers like a gauge reads a tide, and marks the line you should hit by tonight.

Set your gauge

idle — awaiting your numbers

01 — Your numbers

What the tide depends on.

Environment optional — refines your line further

what tidemark reads

Your line is built from five layers: a base for your body weight, a small adjustment for age and height, a boost for however hard you moved today, extra for thin air if you're up high, and a climate adjustment for heat and humidity. Season is just a quick starting point — the temperature and humidity sliders always have the final say.

your line for today

2.6L

≈ 11 cups · 88 oz

≈ 2.8 × 32oz bottles

Base

2.31 L

From your body weight, nudged for age and gender.

Height adjustment

+0.02 L

Taller frames carry a slightly larger fluid volume.

Activity boost

+0.28 L

Extra for sweat lost during your sport, today.

Altitude

+0.00 L

Thinner, drier air above ~1,500m speeds up fluid loss.

Climate

+0.00 L

Heat and humidity both push fluid loss higher.

02 — Pace it out

Eight pours through the day.

tap each drop as you finish it — tracked for today, resets tomorrow

0 of 8 poured today

03 — Log what you actually drink

Not everything is water. That's fine.

Coffee, tea, juice, and other drinks still count — just not always at 100%. Log anything you drink and watch it fill your line.

0 ml of 2.5L logged today