A time marker for the bottle you already own
Time-marked bottles work because the answer to "am I on track?" is printed on the side. You don't need to buy one. Enter your bottle and your own goal, and print a strip cut to its height.
Measure from where the bottle stops curving at the bottom to where it starts narrowing at the top.
This page does not tell you how much to drink. Use the goal you already have, or ask a doctor or pharmacist if a condition or medicine affects your fluids.
Preview. Each line shows the time for every refill.
Putting it on
- Print at 100% scale (not "fit to page"). A centimetre ruler prints beside the strip so you can check it.
- Cut along the dashed outline and hold it against the bottle with the top edge at the full line.
- Cover the whole strip with clear packing tape, wrapping a little past each edge. That keeps it readable through washing-up.
- At any time of day, look for the line with the current time. Water at or below it means you're on pace. Empty means refill and start from the top.
The no-tape version
Dropkin: Water Reminder is an iPhone water tracker built around the bottle you carry, like this strip:
- Save your bottle once, then tap it each time you finish it
- Ounces or millilitres and litres, with round-number bottle sizes in your unit
- Reminders you set, no account, no ads, and it works offline
Free to download for iPhone. Details taken from the app's App Store description, checked 10 November 2026.
Questions
How does a time-marked water bottle work?
Lines down the side of the bottle are labelled with times of day. If the water level is at or below the line for the current time, you are on pace for the amount you chose. Refill when it is empty and start again from the top line.
How much water should I put as my goal?
This page does not set a goal for you. Needs vary with body size, activity, climate and health, so use the amount you already aim for, or ask a doctor or pharmacist if you have a condition or take medicines that affect fluids.
Will the strip print at the right size?
The strip is drawn in real centimetres. Print at 100 percent scale, not fit to page, and check the length against a ruler before taping it on.