Beta hCG Doubling Calculator
In early pregnancy, hCG usually rises steadily, often doubling every two to three days. Enter two beta blood test results with their dates and times to see your doubling time and 48-hour rise, with plain-English context.
First test
Second test
Important, not medical advice. This is a maths tool. hCG levels vary widely between healthy pregnancies, the rise naturally slows as levels climb, and a single pair of numbers cannot diagnose anything. Always interpret your results with your doctor or clinic.
Doubling time
That is roughly every .
Rise over 48h
Hours between
Overall change
As a rough guide, hCG often doubles every 48 to 72 hours early on. Doubling naturally slows once levels pass roughly 1,200 and again past 6,000 mIU/mL, so a slower rise at higher numbers can be perfectly normal. Your clinic interprets this alongside your scans and history.
Next step
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