ThirstyBotA good water drinking schedule splits your daily goal into small drinks of about 7–10 oz (200–300 ml), spread from when you wake up until 1–2 hours before bed. Small, regular drinks are easier to keep up than a lot at once, and they are safer: healthy kidneys can only clear about 0.8–1 liter (27–34 oz) of water an hour. Drinking faster than that can dilute the sodium in your blood.
Daily water drinking schedule (workday, 2 liters / 68 oz)
| Time | Amount | Notes |
|---|---|---|
| 6:30 am | 300 ml (10 oz) | After waking up |
| 8:30 am | 200 ml (7 oz) | Morning coffee or tea counts |
| 10:00 am | 250 ml (8.5 oz) | Mid-morning; easy to forget in an air-conditioned office |
| 11:30 am | 250 ml (8.5 oz) | Before lunch |
| 2:00 pm | 250 ml (8.5 oz) | After lunch |
| 4:00 pm | 250 ml (8.5 oz) | Late afternoon: water instead of coffee helps you sleep |
| 6:30 pm | 300 ml (10 oz) | With dinner |
| 9:00 pm | 200 ml (7 oz) | Keep it small before bed |
| Total | 2,000 ml (68 oz) |
Your own goal may not be 2 liters. It depends on your weight, age, sex and activity (see the chart in how much water should I drink a day). Keep the same times and adjust the amounts. For example, with a goal of 1.6 liters (54 oz), take about 50 ml (2 oz) off each drink.
Tea and coffee count toward your water for the day, according to both the U.S. National Academies and the NHS. Just keep your caffeine within safe limits (see how much caffeine per day is safe).
Drinking water in the morning
A glass of about 250–300 ml (8–10 oz) after you get up is plenty. It is an easy habit to keep, and it gets part of your goal done early. That said, official guidance does not require drinking at any particular time. What matters is your total for the day and spreading it out.
Drinking water before meals (and for weight loss)
In a study of 48 overweight adults aged 55–75 on a reduced-calorie diet, those who drank an extra 500 ml (17 oz) of water before each main meal lost about 2 kg (4.4 lb) more over 12 weeks than those who only dieted. Water did not cause weight loss on its own. The effect was seen alongside the diet.
If you want to try this, count those 500 ml toward your daily goal rather than adding them on top. Don’t do it if a doctor has told you to limit fluids.
Drinking water before bed
Keep it small, about 150–200 ml (5–7 oz), and finish 1–2 hours before you go to sleep so you are less likely to wake up to pee. If you have been drinking steadily all day, there is no need to catch up in the evening.
Workout days and hot days
Workout days: keep the schedule above and add drinks before, during and after your session. The amounts are in drinking water before, during and after a workout.
Hot days: the NHS says you may need more fluid in hot environments. For people working in the heat, NIOSH (part of the CDC) advises:
- 1 cup (8 oz) every 15–20 minutes while working, and drink before you feel thirsty.
- No more than 48 oz (1.5 quarts, about 1.4 liters) an hour.
If you have been sick or sweated heavily, plain water does not replace lost salts (see signs of dehydration).
Do you need a schedule, or can you just drink when thirsty?
According to the U.S. National Academies, most healthy people get enough water by drinking when they are thirsty. A schedule helps most when:
- You forget to drink because you are busy, or you sit in air conditioning all day.
- It is hot, or you work outdoors.
- You are older. The European Society for Clinical Nutrition and Metabolism (ESPEN) considers all older adults at risk of low intake. It advises older women to drink at least 1.6 liters (54 oz) and older men at least 2.0 liters (68 oz) a day. Urine colour is not a reliable guide in older adults, so counting glasses works better.
If you have heart failure, severe kidney disease or low blood sodium, or have been told to limit fluids, follow your doctor’s amount, not this schedule.
Set up reminders in ThirstyBot
In Adjust schedule & water reminder, you can set reminders at the exact times in the table above and set your Sleep hours so the app stays quiet at night. The app divides your daily goal into an amount for each reminder. That goal is based on your body, and you can try it first in the water intake calculator.
ThirstyBot does not replace medical advice. If you have a medical condition, ask your doctor how much water is right for you.
Sources
- National Academies – Report sets dietary intake levels for water, salt, and potassium (2004)
- NHS – Water, drinks and your health
- NIOSH / CDC – Heat Stress: Hydration
- Dmitrieva et al. – eBioMedicine 92:104638 (2023)
- Dennis et al. – Water before meals during a weight-loss diet, Obesity (2010)
- ESPEN – Practical guideline: clinical nutrition and hydration in geriatrics (2022)
