hCG Levels Calculator — Pregnancy by Week
Enter your hCG blood test result and the number of weeks since your last menstrual period (LMP) to see how your level compares with published reference ranges.
Context
mIU/mL
weeks
Within expected range
- 1
Approximate median (geometric mean)
√(18 × 7,340) = 363Geometric mean of the published low and high reference values used as an approximate midpoint. - 2
% of median
(1,200 ÷ 363) × 100 = 330
How does this calculator work?
hCG is produced by the placenta, rising rapidly in the first trimester and peaking at weeks 10–12. Typical levels at week 5 are 18–7,340 mIU/mL; at week 9–12, 25,700–288,000 mIU/mL. Enter your measured hCG and gestational week to see if the value falls within published reference ranges. Always interpret with a clinician.
Formula
How this is calculated
Human chorionic gonadotropin (hCG) is produced by the placenta shortly after a fertilised egg implants. Levels rise rapidly in the first trimester, typically doubling every 48–72 hours in early pregnancy, peak around weeks 10–12, then gradually decline for the remainder of the pregnancy. Measuring serum (blood) hCG is more accurate than urine tests and is reported in milli-international units per millilitre (mIU/mL).
This calculator compares your value against approximate typical ranges from published clinical data (American Pregnancy Association and similar references). Because the ranges span several orders of magnitude even for a healthy pregnancy — for example, weeks 9–12 range from 25,700 to 288,000 mIU/mL — the RangeMeter uses a logarithmic scale to show where your value falls within the band. The "% of median" uses the geometric mean of the published low and high as a rough midpoint.
Important limitations: reference ranges differ substantially between laboratories, assays and individuals. A single value outside the listed range is not diagnostic on its own. Serial measurements (checking how quickly the level rises) are more clinically meaningful than a single number. Always review results with your healthcare provider.
Frequently asked questions
At 4 weeks, typical values are 5–426 mIU/mL. By week 6 they reach 1,080–56,500 mIU/mL, and peak around weeks 9–12 at 25,700–288,000 mIU/mL. The enormous ranges reflect genuine biological variation; what matters most is that levels rise appropriately, doubling roughly every 2–3 days in early pregnancy.
Not necessarily. Labs use different assays with different reference intervals, and individual variation is huge. A level outside this calculator's range does not confirm a problem. Your doctor will consider serial measurements, ultrasound findings, and clinical symptoms together.
Multiple pregnancies tend to produce higher hCG than singleton pregnancies, but overlap is so large that hCG alone cannot reliably diagnose multiples. Ultrasound around 6–8 weeks is the definitive way to confirm the number of embryos.
Also known as
TG we-Calculate Editorial Team. (2026). hCG Levels Calculator — Pregnancy by Week [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/hcg-levels-calculator
TG we-Calculate Editorial Team. "hCG Levels Calculator — Pregnancy by Week." TG we-Calculate. 2026. https://we-calculate.com/calculator/hcg-levels-calculator.
TG we-Calculate Editorial Team, "hCG Levels Calculator — Pregnancy by Week," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/hcg-levels-calculator
@misc{wecalculate_hcg_levels_calculator, title = {hCG Levels Calculator — Pregnancy by Week}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/hcg-levels-calculator}}, year = {2026}, note = {TG we-Calculate} }
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