To time contractions, you need two measurements: how long each one lasts (duration) and how far apart they are (frequency). Start a timer when a contraction begins and stop it when that contraction ends to get the duration. Then measure from the start of that contraction to the start of the next one to get the frequency. Those two numbers, tracked over an hour or more, tell you whether labor is progressing and when it’s time to head to the hospital.
What You’re Actually Measuring
Contraction timing tracks two things. Duration is the length of a single contraction from the moment your belly tightens to the moment it relaxes. Frequency is the gap between contractions, measured from the beginning of one to the beginning of the next, not from the end of one to the start of the next. That distinction matters because it gives a more accurate picture of your labor pattern.
Early labor contractions typically last 30 to 45 seconds and come anywhere from 5 to 20 minutes apart. As labor progresses into the active phase, contractions lengthen to about 60 to 90 seconds each and arrive every 2 to 5 minutes. Tracking both numbers over time lets you see the trend, which is more useful than any single measurement.
Step-by-Step: Timing With a Clock or Phone
You can time contractions with nothing more than a clock with a second hand, a stopwatch, or the timer on your phone. Here’s the process:
- Note the start time. When you feel tightening or pain begin, write down the exact time (including seconds if possible) and start your timer.
- Note the end time. When the contraction fully releases, stop the timer. The elapsed time is your duration.
- Wait for the next one. When the next contraction starts, write down that start time. The gap between the two start times is your frequency.
- Repeat for at least an hour. A single pair of contractions doesn’t tell you much. You need a string of them to see whether they’re getting closer together and longer.
Keep a simple log. A notes app, a piece of paper, or even a text thread works fine. Write down three columns: start time, end time, and minutes since the last one started. After five or six contractions, you’ll see a pattern forming or you’ll notice the contractions are still irregular.
Contraction Timer Apps
Contraction timer apps do the math for you. You tap a button when a contraction starts and tap again when it ends, and the app calculates duration, frequency, and running averages automatically. Most good apps display a simple dashboard so you can see your pattern at a glance. Some include features like color-coded indicators that change when your pattern suggests active labor, the ability to share data with a partner’s phone, and milestone tracking that doubles as a basic birth timeline.
The best app is whichever one feels intuitive under stress. Look for a clean interface with large buttons, since you won’t want to navigate menus mid-contraction. Several free options work well, so there’s no need to pay for premium features unless you want extras like data export.
The 5-1-1 Rule
The most widely used guideline for when to go to the hospital is the 5-1-1 rule: contractions are 5 minutes apart, each lasting about 1 minute, and the pattern has held steady for at least 1 hour. This rule applies primarily to first-time pregnancies, where labor tends to progress more slowly and there’s generally more time before delivery.
If you’ve given birth before, your provider may tell you to come in sooner, sometimes at 7 or 8 minutes apart, because subsequent labors often move faster. Either way, confirm the specific guideline your provider recommends, since some practices use slightly different thresholds like 4 minutes apart instead of 5.
True Labor vs. Braxton Hicks
Timing contractions is also the best way to tell whether you’re in real labor or experiencing Braxton Hicks contractions, the “practice” contractions that can start weeks before delivery. The key differences show up clearly in your log:
- Pattern. True labor contractions come at regular intervals and get closer together over time. Braxton Hicks contractions are irregular with no consistent pattern.
- Progression. Real contractions grow longer and more intense as labor advances. Braxton Hicks stay about the same or fade out entirely.
- Response to rest. If you lie down, drink water, and the contractions stop, they’re almost certainly Braxton Hicks. True labor contractions continue regardless of rest, movement, or position changes.
If you’re unsure, try drinking a full glass of water and resting for 30 minutes while continuing to time. Braxton Hicks will typically space out or disappear. Real labor won’t.
What Active Labor Looks Like on Your Log
Active labor begins when contractions settle into a rhythm of every 2 to 5 minutes, each lasting around 60 seconds or longer, and they demand your full attention. You’ll notice you can no longer talk through them easily. On your tracking sheet, the frequency column will show numbers getting steadily smaller over time, and the duration column will creep upward toward a minute or beyond.
The transition from early labor to active labor isn’t always a clean line. You might see contractions at 7 minutes apart for an hour, then 5 minutes, then briefly back to 7 before settling at 4. That’s normal. The overall trend matters more than any single interval. If the general direction is shorter gaps and longer contractions, labor is progressing.
When Timing Takes a Back Seat
Certain situations call for immediate contact with your provider regardless of what your contraction log shows. Strong vaginal bleeding, an urge to push, or a sudden stop in fetal movement all override the numbers. If your water breaks and the fluid is green, brown, or yellow instead of clear, that also warrants a call right away. When you do call, report when symptoms started, how far apart and how long your contractions have been, whether you’re bleeding, what color any fluid is, and whether the baby’s movement pattern has changed.
Pain that feels unbearable or fundamentally different from the tightening pattern of contractions is another reason to check in early. Contraction timing is a useful tool, but it’s one data point among several, and some warning signs matter more than whether you’ve hit the 5-1-1 threshold.