Contraction timer

Tap the big button when you feel a contraction begin, and tap it again when it fades. That's it. For every contraction the timer records the start time and length, and it updates three numbers for the last 60 minutes:

• Contractions in the last hour
• Average length of each contraction
• Average frequency, measured from the start of one contraction to the start of the next

Below that, a table lists your latest 30 contractions with their start time, length and the time since the previous one started. Tapped by mistake? Use Undo last. When you're done, Download (CSV) saves the whole list as a spreadsheet you can show your OB-GYN or midwife, and Start over clears it.

Everything runs in your browser, and nothing is sent to a server. The list is saved in this browser's local storage, so it's still there if you close the tab. Clearing your browsing data deletes it.

The two numbers people mix up most are length (how long one contraction lasts) and frequency (how far apart they are). Frequency is always counted from the start of one contraction to the start of the next, so it includes the contraction itself.

Start	Length	Since previous start
10:02:10 PM	0:48	–
10:08:05 PM	0:55	5:55
10:13:20 PM	1:02	5:15
10:18:15 PM	0:58	4:55

Here the contractions last about 1 minute and come about 5 minutes apart. The rest between them is only about 4 minutes, but you'd still describe them as "5 minutes apart." Your provider will usually ask for exactly these two numbers, plus how long the pattern has lasted.

Many US hospitals teach the 5-1-1 rule as a rule of thumb for when to come in: contractions about 5 minutes apart, each lasting about 1 minute, for at least 1 hour. It's a common patient-education guide, not an official ACOG guideline, and your own provider may give you different instructions. Follow theirs.

The timer shows a 5-1-1 notice when, over the last hour, you've logged at least 8 contractions across 55 minutes or more, they average 5 minutes apart or less with no gap longer than 7 minutes, and they average at least 50 seconds long. Real contractions are never perfectly even, so the check allows some wiggle room.

A second, more urgent warning appears if you log 6 or more contractions within 10 minutes, or if one lasts longer than 2 minutes. That threshold comes from the UK's NHS guidance on when to call the maternity unit urgently. If you see it, call your labor and delivery unit right away.

According to ACOG, true labor contractions come at regular intervals, get closer together over time, and each lasts about 60 to 90 seconds. Early labor can be slow and irregular; the NHS notes there's no set pattern to how many contractions you get or how long they last at that stage.

Contractions that stay irregular or don't get closer together are less likely to mean active labor. That's exactly what a timed log helps you see. Still, you don't need to be sure before you call. If you think you're in labor, ACOG's advice is to call your OB-GYN.

While you wait, keep an eye on your baby's movements. If you're not in labor yet, the kick counter can help you track them, and pregnancy week by week shows what's typical for your stage. Not sure how many weeks you are? Check with the due date calculator.

Some signs matter more than any contraction pattern. Call your provider or labor and delivery unit, or go to the hospital, if:

• your water breaks, even if you're not having contractions
• you have heavy vaginal bleeding
• you have constant, severe pain with no relief between contractions
• your baby is moving less than usual
• you have regular contractions before 37 weeks (that's before term)
• you're vomiting with contractions, feel strong rectal pressure, or can't walk or talk through a contraction

If the baby is coming now or you're bleeding heavily, call 911. This timer is informational and isn't a substitute for medical advice; your OB-GYN or midwife's instructions always come first.