Choose how many weeks pregnant you are to see the typical beta hCG range for that week — then remember that these ranges are extremely wide, and the trend matters far more than any single number.
Human chorionic gonadotropin, almost always shortened to hCG, is the hormone made by the cells that go on to form the placenta. It starts to appear shortly after a fertilized egg implants in the lining of the uterus, and it rises quickly in the first weeks of pregnancy. It is the very hormone that home pregnancy tests look for in urine, and the one a quantitative blood test — usually called a beta hCG, or simply a "beta" — measures precisely in mIU/mL (milli-international units per milliliter).
Providers measure hCG for a few gentle, practical reasons. Early on, before an ultrasound can see much, hCG offers one of the only windows into how a pregnancy is developing. A first beta confirms that hCG is present and gives a rough sense of how much. But because normal levels vary so much from one person to the next, that first number rarely means much by itself. What your care team is usually watching for is the pattern across two draws taken about 48 hours apart. This page is a reference for the typical numbers — not a diagnosis, and never a substitute for your provider's read on your own results.
The table below shows typical beta hCG ranges by week of pregnancy, counting from the first day of your last menstrual period (LMP). These reference values come from the American Pregnancy Association. The first thing most people notice is how huge the ranges are — and that is exactly the point worth sitting with.
| Weeks since last period | Typical hCG range (mIU/mL) |
|---|---|
| 3 weeks | 5 – 50 |
| 4 weeks | 5 – 426 |
| 5 weeks | 18 – 7,340 |
| 6 weeks | 1,080 – 56,500 |
| 7–8 weeks | 7,650 – 229,000 |
| 9–12 weeks | 25,700 – 288,000 |
| 13–16 weeks | 13,300 – 254,000 |
| 17–24 weeks | 4,060 – 165,400 |
| 25–40 weeks | 3,640 – 117,000 |
Notice how hCG climbs steeply through the early weeks, peaks somewhere around weeks 9 to 12, and then gradually settles to a lower, steadier level for the rest of pregnancy. That later decline is completely expected — it is not a sign that anything is wrong. It simply reflects how the hormone behaves once the placenta is well established.
This is the most important idea on the page, so it is worth saying plainly: a normal, healthy pregnancy can sit almost anywhere within the range for its week. Look at 5 weeks — roughly 18 to 7,340 mIU/mL. That is a spread of more than 400-fold. Two people with perfectly healthy pregnancies, at the exact same gestational age, can have wildly different numbers, and both are entirely normal.
There are good reasons for all that variation. Dating from a last period is often off by several days, so a pregnancy you think is "6 weeks" might really be 5 or 7. Implantation timing differs from person to person. Labs and assays vary slightly in how they measure. And simple human biology means the hormone rises on its own schedule. Because the ranges overlap so heavily from one week to the next, a single hCG value cannot reliably date a pregnancy or predict how it will turn out. Comparing your number to a friend's, or to a post in an online forum, will tell you almost nothing — and can cause a lot of needless worry. Where your value falls within the range matters far less than whether it is rising as it should for you.
If a single value says little, what does carry information? The trend. In early pregnancy, hCG tends to rise in a predictable way: while levels are still relatively low, it roughly doubles every 48 to 72 hours. That is why providers so often order two draws about two days apart — the change between them reveals far more than either number alone.
Doubling naturally slows as levels climb higher, and it is worth knowing that "doubling" is a rule of thumb rather than a strict cutoff. Some healthy pregnancies rise more slowly than average, especially once hCG is already high. If you have two beta results with their dates and times, our hCG doubling time calculator will do the math for you and show your doubling time and percent change — numbers you can bring straight to your appointment. Think of the trend as the story, and any single value as just one word in it.
One of the most common questions is whether a high number means twins. The honest answer is: it might, but hCG cannot tell you. In some twin and higher-order multiple pregnancies, hCG does run higher than average — there is, after all, more placental tissue producing the hormone. But the normal range for a single pregnancy is already so wide that it overlaps almost completely with twin values.
In practice, that means a high beta is not proof of twins, and a number in the usual range does not rule them out. hCG simply is not a diagnostic test for how many babies there are. The only way to know for certain is an ultrasound, which can count heartbeats and gestational sacs directly. If you are curious or hopeful about twins, that is a lovely conversation to have with your provider at your first scan — not something to try to read from a lab slip.
If your numbers are not rising the way the ranges above suggest — or if a second draw is lower than the first — we want to be both gentle and honest with you. Late in the first trimester, a plateau is normal and expected, since hCG has usually peaked and begun to settle. Earlier on, though, a fall or a stall is something your provider will want to know about soon. It can be an early sign that a pregnancy is not progressing, including a possible miscarriage or an ectopic pregnancy (one that has implanted outside the uterus, which needs prompt medical attention).
Please hear this clearly, though: a slower-than-expected rise or a single lower value is a reason for follow-up, not a verdict. Lab timing and normal variation can play a role, and some healthy pregnancies simply do not follow the textbook curve. Only a provider — using serial hCG measurements together with ultrasound — can interpret what your numbers actually mean. If you have significant bleeding, one-sided or shoulder-tip pain, or feel faint, contact your provider or emergency services right away rather than waiting for the next blood draw. However your numbers look today, you deserve real answers and real support, and those come from your care team.
Normal hCG ranges are enormously wide and overlap heavily from week to week. For example, at 5 weeks anything from about 18 to 7,340 mIU/mL can be normal, and at 6 weeks the typical range is roughly 1,080 to 56,500 mIU/mL. Because two healthy pregnancies at the same gestational age can have very different numbers, a single value cannot confirm how far along you are or whether all is well — the trend between two draws matters far more.
Not reliably. hCG can run higher in some twin and multiple pregnancies, but the normal ranges for single pregnancies are so wide that they overlap almost completely with twin values. A high number is not proof of twins, and a number in the usual range does not rule them out. Only an ultrasound can confirm how many babies there are.
A value at the low end of the range for your week is often completely normal — dating from a last period is frequently off by several days, and a pregnancy that implanted a little later will simply have lower numbers. A single low value does not diagnose a problem. Your provider will look at whether hCG is rising appropriately over 48 hours and, once levels are high enough, use ultrasound for a much clearer picture.
In early pregnancy, providers often order two beta hCG draws about 48 hours apart to see how quickly the level is rising, since the trend carries most of the information. There is usually no need to check repeatedly beyond that — once hCG is high enough, an ultrasound gives far clearer answers than more blood tests. How often to test is a decision your provider makes based on your history and symptoms.
Yes. Because normal ranges are so wide, a value that looks "normal" for your week does not by itself confirm a healthy, ongoing pregnancy — and an unusual value does not confirm the opposite. This is exactly why a single number is rarely meaningful on its own. Only your provider, using serial hCG measurements together with ultrasound, can interpret what your results mean for your pregnancy.