Why hCG is counted from ovulation, not your period
hCG is produced by the embryo once it implants, and implantation happens 6 to 12 days after ovulation. Counting from your last period adds the variable follicular phase on top, which is why two people at "4 weeks" can have very different hCG levels. Days past ovulation removes that noise.
After implantation, hCG roughly doubles every 48 hours in the first weeks, so the table climbs steeply: a median of about 5 mIU/mL at 10 DPO becomes about 50 by 14 DPO and several hundred by 18 DPO. Even so, the range at any DPO spans roughly tenfold because implantation day varies.
Using the numbers well
Use the range to decide when to test, not to grade a result. A single beta below the range usually means later implantation or a slightly off ovulation date. What reassures clinicians is the trend between two tests, which the hCG doubling calculator works out. To count your DPO precisely first, use how many DPO am I.
Frequently asked questions
What should hCG be at 14 DPO?
Around 50 mIU/mL is a typical serum value at 14 DPO, with a normal range from about 15 to 150. The spread is wide because implantation can happen anywhere from 6 to 12 DPO, which shifts the whole curve by days. A single value inside the range, or even a little outside it, tells you far less than the rise between two tests taken 48 hours apart.
At what DPO will a pregnancy test be positive?
An early-detection test (10 mIU/mL) can show a faint line from about 10 DPO if implantation was on the early side. A standard 25 mIU/mL test is usually positive by 12 to 14 DPO. Digital and less sensitive tests may need 14 DPO or later. Urine hCG lags serum slightly, and first-morning urine is the most concentrated.
My hCG is lower than the range for my DPO. Is something wrong?
Not necessarily. The most common reasons are later implantation and an ovulation date that is a day or two off, both of which put you at an earlier real DPO than you think. What matters is whether the level roughly doubles every 48 to 72 hours in early pregnancy. Your clinician will usually repeat the test rather than judge one number.
Can hCG tell me how many weeks pregnant I am?
Only very roughly. Reference ranges by week overlap heavily: 100 mIU/mL could be week 4 or week 5. Enter your value and the calculator lists every week whose range includes it. Dating by last period, and especially by early ultrasound, is far more accurate than dating by hCG.
Does a high hCG mean twins?
Sometimes, but a single high value is weak evidence. Early implantation and normal variation produce high numbers in single pregnancies all the time. Twins are confirmed by ultrasound, usually from about 6 to 7 weeks, not by hCG.
These calculators give estimates based on cycle averages and standard formulas. They are for general information only and are not medical advice. For anything concerning your health or pregnancy, talk to a qualified healthcare provider.