Pregnancy tool

Contraction Timer

Tap to time each contraction. The tool tracks duration and frequency, shows your last-hour averages, and flags the 5-1-1 pattern that often signals it's time to call your provider.

Last reviewed 20 May 2026

Ready

0:00

Tap Start as a contraction begins, Stop as it ends.

Contraction log

No contractions logged yet. Tap "Start contraction" above to begin.

Your log is saved on this device only and persists if you refresh. If you have any signs of labor before 37 weeks, heavy bleeding, your water breaks, reduced fetal movement, or you simply feel something is wrong — contact your provider right away regardless of what the timer shows. Medical disclaimer.

How to use this timer

  1. When a contraction begins, tap Start contraction.
  2. When it eases off, tap Stop contraction.
  3. Repeat for every contraction. Don't worry about being perfectly precise — the pattern over time is what matters.
  4. Watch the last-hour averages and the 5-1-1 status banner.
  5. Follow the specific instructions your provider gave you about when to call or come in.

Background: the science of timing contractions

Duration vs. frequency

Two numbers describe a contraction pattern. Duration is how long a single contraction lasts. Frequency is the time from the start of one contraction to the start of the next — by convention, start-to-start, not the rest gap in between. As labor progresses, contractions typically get longer (duration up), closer together (frequency down), and stronger.

Why 5-1-1?

The 5-1-1 rule — contractions ~5 minutes apart, ~1 minute long, for ~1 hour — is a practical threshold many providers use to identify when active labor is likely established for a first-time, full-term, low-risk pregnancy. It is a rule of thumb, not a law of nature: some providers use 4-1-1 or 3-1-1, and instructions differ for people who have given birth before (labor can move faster) or who have specific risk factors.

True labor vs. Braxton Hicks

Braxton Hicks contractions are the uterus "practising". They tend to be irregular, don't progressively shorten the interval, often fade with hydration, rest, or a change of position, and don't ramp up in intensity. True labor contractions are regular, progressive, and unaffected by what you do. Timing them is the clearest way to tell the difference.

How to interpret your results

  • Irregular, not progressing: likely Braxton Hicks — rest, hydrate, and re-time later.
  • Regular and getting closer/longer/stronger: labor may be progressing — note the trend.
  • 5-1-1 reached: the banner turns red — for many people this is the call-your-provider point.

The timer only describes the pattern. It cannot examine your cervix or assess dilation — only your care team can confirm what stage of labor you're actually in.

What this tool does NOT do

  • It does not diagnose labor or measure cervical dilation.
  • It does not replace your provider's specific instructions.
  • It does not detect preterm labor, complications, or fetal distress — seek care immediately for any warning sign regardless of the timer.

Sources

  • American College of Obstetricians and Gynecologists — patient guidance on "How to tell when labor begins".
  • ACOG. Approaches to Limit Intervention During Labor and Birth (re: latent vs. active labor definitions).
  • National Health Service (NHS) — Signs that labour has begun.

See our methodology. This tool is not a substitute for medical advice — read the medical disclaimer.

Frequently asked questions

What is the 5-1-1 rule?
5-1-1 is a widely used guideline for when active labor may be established: contractions about 5 minutes apart (start to start), each lasting about 1 minute, sustained for at least 1 hour. For many people this is the cue to call their provider or head to the birth location. Your own provider may give you a different rule (some use 4-1-1 or 3-1-1, or different instructions for a second baby or a previous fast labor) — always follow the specific guidance you were given.
How does the timer measure frequency?
Frequency is the time from the START of one contraction to the START of the next — not the gap between them. That's the clinical convention. So if a contraction starts at 10:00 and the next starts at 10:05, the frequency is 5 minutes even though the actual rest gap was shorter.
How do I use it?
Tap 'Start contraction' the moment a contraction begins and 'Stop contraction' when it eases off. Repeat for each one. The tool logs duration and frequency, shows rolling averages for the last hour, and tells you whether the 5-1-1 pattern has been reached.
Is my log saved if I close the tab?
Yes. The log is saved in your browser's local storage on this device, so a refresh or accidental tab close won't lose it. It is not synced to an account or another device. Use the 'Clear' button to wipe the log when you no longer need it.
What's the difference between true labor and Braxton Hicks?
Braxton Hicks ('practice') contractions are usually irregular, don't get closer together, often ease with rest, position change, or hydration, and don't increase in intensity. True labor contractions become regular, get closer together, last longer, grow stronger, and continue regardless of what you do. The timer helps you see the pattern — regularity and progression point toward true labor.
When should I contact my provider regardless of the timer?
Contact your provider or seek care immediately — no matter what the timer shows — if you have: any signs of labor before 37 weeks, your water breaks, heavy or bright-red vaginal bleeding, severe constant abdominal pain, reduced fetal movement, severe headache or vision changes, or simply a feeling that something is wrong.
Does the timer work offline?
The timer runs entirely in your browser, so once the page has loaded it keeps working even if your connection drops. Your log stays in local storage on the device.