Period blood colour: what is normal?

Your period blood is not always the same shade, even within one period. The good news is that a lot of variety is normal. The honest news is that there is not much formal research on colour, so doctors look at the whole picture: how heavy it is, how long it lasts, any smell, and how you feel.

What the NHS says

The NHS says that when your period is at its heaviest the blood will be red, and that on lighter days it may be pink or brown. Cleveland Clinic adds that blood can range from pink to brown, and may even look rust-like.

Common shades and what they usually mean

• Bright or dark red: the heaviest flow, when blood is leaving quickly.
• Brown or very dark: commonly explained as older blood that has had time to change colour. Common at the start or end of a period and on light days.
• Pink: often a light flow, at the start or end of a period or on lighter days (the NHS says blood on lighter days may be pink or brown).
• Small jelly-like clots: often normal on heavy days. Large ones are different (see the clots guide).

Changes worth getting checked

• Grey-white, thin, watery discharge with a strong fishy smell: the NHS links this pattern to bacterial vaginosis (BV), which is common and treatable.
• Green, yellow or frothy discharge: the NHS says this may be trichomoniasis, an infection that needs treatment.
• Any bleeding with pain in the pelvis, tummy pain, or a high temperature.
• A big change from your normal: much heavier, much longer, or bleeding between periods.