Pregnancy Week Tracker
Find how far along you are in weeks and which trimester you are in.
About Pregnancy Week Tracker
Gestational age counts the days since the first day of the last menstrual period, converted into completed weeks. Pregnancy is roughly forty weeks, with trimesters beginning at week one and at weeks fourteen and twenty-seven. Weeks of pregnancy are the common language of prenatal milestones and screening schedules, so converting a calendar date into weeks makes appointments easier to follow.
Formula
Pregnancy Week Tracker
Weeks pregnant = days since the last period / 7; trimesters split at weeks 13 and 27
- LMP
- First day of the last menstrual period
- gestational age
- Time elapsed since the LMP
Worked example
With the default values below, Pregnancy Week Tracker returns Days Pregnant of 248. Change any input above and every figure here is recalculated in your browser.
Inputs used
- LMP year
- 2,025
- LMP monthaccepts 1–12
- 12
- LMP dayaccepts 1–31
- 10
- Today's year
- 2,026
- Today's monthaccepts 1–12
- 8
- Today's dayaccepts 1–31
- 15
Results
- Days Pregnant
- 248
- Pregnancy Week
- 36
- Day into Week
- 4
- Trimester
- Third trimester
- Weeks Remaining
- 4
Step by step
- 1Values used
- 2Pregnancy Week Tracker
- 3Days Pregnant= 248
- 4Pregnancy Week= 36
- 5Day into Week= 4
- 6Trimester= Third trimester
- 7Weeks Remaining= 4
Assumptions and limits
- The result is derived only from the 6 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to whole numbers, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Pregnancy Week Tracker calculated?
Weeks pregnant = days since the last period / 7; trimesters split at weeks 13 and 27 Gestational age counts the days since the first day of the last menstrual period, converted into completed weeks. Pregnancy is roughly forty weeks, with trimesters beginning at week one and at weeks fourteen and twenty-seven.
Why does Pregnancy Week Tracker matter?
Weeks of pregnancy are the common language of prenatal milestones and screening schedules, so converting a calendar date into weeks makes appointments easier to follow.
What values do I need to enter?
This calculator takes 6 inputs: LMP year, LMP month, LMP day, Today's year, Today's month, Today's day. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.