Pregnancy Week Calculator (How Far Along?)
Exactly how many weeks-and-days pregnant you are today, from LMP or due date, with trimester placed.
Obstetric weeks are *completed* weeks — '12 weeks 5 days' is medically still week 12, though colloquially you're 'in your 13th week'. That off-by-one trips up almost everyone comparing apps. Trimester boundaries also vary by source; the 13/28 convention here is the commonest clinical one.
Formula
For general information only. Pregnancy and infant care decisions must be guided by your treating clinician or midwife — always defer to their assessment.
Exactly how many weeks-and-days pregnant you are today, from LMP or due date, with trimester placed. The Pregnancy Week Calculator (How Far Along?) is a free, private how far along am i tool — every result computes instantly in your browser with no sign-up and no data upload.
About Pregnancy Week Calculator (How Far Along?)
Obstetric weeks are *completed* weeks — '12 weeks 5 days' is medically still week 12, though colloquially you're 'in your 13th week'. It applies weeks = (today − LMP) ÷ 7; EDD entry converts via LMP = EDD − 280. Use the Pregnancy Week Calculator (How Far Along?) to get an instant, clearly-explained result with the working shown step by step — free, private and with the source method cited.
How to use Pregnancy Week Calculator (How Far Along?)
- 1Enter your details in the Pregnancy Week Calculator (How Far Along?) input fields above.
- 2The result updates instantly with the working and reference bands shown.
- 3Adjust any value to explore how it changes the outcome — it's free and unlimited.
Why use Pregnancy Week Calculator (How Far Along?)?
- ✓Instant how far along am i result that recomputes as you type — no waiting, no page reloads
- ✓100% client-side: your health data never leaves your browser
- ✓Shows the actual formula and your numbers substituted in, so you can see exactly how the result is reached
- ✓Based on published, citable sources (ACOG — how pregnancy is dated and counted)
- ✓Free forever with no sign-up, account or app install
Frequently asked questions
How does the Pregnancy Week Calculator (How Far Along?) work?+
Obstetric weeks are *completed* weeks — '12 weeks 5 days' is medically still week 12, though colloquially you're 'in your 13th week'. The calculation uses the formula: weeks = (today − LMP) ÷ 7; EDD entry converts via LMP = EDD − 280. Everything runs instantly in your browser as you type — your inputs are never uploaded.
Is the Pregnancy Week Calculator (How Far Along?) accurate, and what is it based on?+
The method is traceable to authoritative sources: ACOG — how pregnancy is dated and counted. Results are estimates — individual variation always applies, so treat the output as a well-grounded starting point.
Is the Pregnancy Week Calculator (How Far Along?) free and private?+
Yes. It's completely free with no sign-up, and all computation happens locally in your browser, so none of your health data ever leaves your device.
Can I use this for medical decisions?+
This tool is informational only. Always defer to your treating clinician or midwife for pregnancy and infant care decisions.
What can I use the Pregnancy Week Calculator (How Far Along?) for?+
It's commonly used for how far along am i, pregnancy week calculator, weeks pregnant. Exactly how many weeks-and-days pregnant you are today, from LMP or due date, with trimester placed.
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