hCG calculator and hCG levels by week
In early pregnancy hCG usually doubles every 48 to 72 hours. Normal levels vary hugely between women, so a single result means little; the change between two tests 48 hours apart is more useful. Enter two results to see your doubling time.
hCG levels by week
These are typical ranges in mIU/mL, counting weeks from the first day of your last period. They are very wide: many healthy pregnancies fall outside them, and labs may use different ranges.
| Weeks since last period | hCG range (mIU/mL) |
|---|---|
| 3 weeks | 5 to 50 |
| 4 weeks | 5 to 426 |
| 5 weeks | 18 to 7,340 |
| 6 weeks | 1,080 to 56,500 |
| 7 to 8 weeks | 7,650 to 229,000 |
| 9 to 12 weeks | 25,700 to 288,000 |
| 13 to 16 weeks | 13,300 to 254,000 |
| 17 to 24 weeks | 4,060 to 165,400 |
| 25 to 40 weeks | 3,640 to 117,000 |
Commonly published reference ranges. Non-pregnant: under 5 mIU/mL. Your lab report shows its own reference range.
What hCG is
Human chorionic gonadotropin (hCG) is the hormone made by the developing placenta after the embryo implants. It keeps the pregnancy going in the first weeks, and it's what pregnancy tests detect. Blood tests measure the exact amount; urine tests only show whether it's there.
When doctors check hCG
- After IVF or fertility treatment, to confirm pregnancy
- If you have bleeding or pain in early pregnancy
- To check for an ectopic pregnancy, usually together with a scan
- After a miscarriage, to make sure levels return to zero
hCG questions
How fast should hCG rise in early pregnancy?
In a healthy early pregnancy, hCG usually doubles every 48 to 72 hours while levels are below about 1,200 mIU/mL. After that the rise slows, and it peaks around 8 to 11 weeks before falling and levelling off.
What is a normal hCG level at 4 weeks?
Anywhere from about 5 to 426 mIU/mL. Ranges are very wide, so a single number tells you little. Your doctor looks at how the level changes over 48 hours, and at scan results.
What does a low hCG level mean?
A low single reading may simply mean it's earlier in the pregnancy than you thought. A level that rises slowly, stays flat or falls can be a sign of miscarriage or ectopic pregnancy, so your doctor will monitor it, often with a scan.
Can high hCG mean twins?
Twin pregnancies often have higher hCG levels, but levels overlap so much that hCG can't confirm twins. Only a scan can.
When can a home test detect hCG?
Most home tests detect hCG at about 25 mIU/mL, usually from the day your period is due.
This calculator is for information only. Always discuss your results with your doctor.