When to Take a Pregnancy Test

Find the earliest day to take a pregnancy test and the day it's most reliable.

First day of last period	2026-10-25
Cycle length	28 days
Date of unprotected sex (optional, for timing)	2026-11-08

First day of last period

Cycle length

days

Date of unprotected sex (optional, for timing)

Most reliable from

Sun 22 November

That's the day your period is due. Sensitive tests may show a result from about Wed 18 November (around 10 days after ovulation on Sun 8 November), but many pregnancies aren't detectable that early. The NHS also suggests testing 21 days after unprotected sex (Sun 29 November).

To ovulation: 14 daysTo missed period: 14 days

Ovulation
Sun 8 November
Earliest test
Wed 18 November
Period due
Sun 22 November

About the When to Take a Pregnancy Test

Home tests detect hCG, which is made after the embryo implants, usually 8–10 days after ovulation. Levels double roughly every two days, so most tests are reliable from the first day of a missed period. The NHS says you can do a test from the first day of a missed period, or 21 days after unprotected sex if you don't know when your period is due.

The formula

Reliable from = first day of last period + cycle length

Worked example

Example: Most reliable from = Sun 1 February

Inputs: First day of last period: 1 January 2026; Cycle length: 31 days; Date of unprotected sex (optional, for timing): 1 January 2026.
Formula: Reliable from = first day of last period + cycle length
Result: Most reliable from = Sun 1 February

Questions people ask

Should I use first-morning urine?

Early on, yes: it's the most concentrated.

Negative but no period?

Test again in 2–3 days; if still negative and no period, see a doctor.

Sources

NHS: Pregnancy tests