What do the colours of the Türkiye flag mean?

Red: the field; traditionally the blood of the fallen. White: the crescent and star.

How do you tell the Türkiye flag from the Tunisia one?

Tunisia places its crescent and star inside a white disc at the centre of the red field.

When was the Türkiye flag adopted?

The current design dates from 1936, and its official ratio is 2:3.

The flag of Türkiye

A red field with a white crescent and a white five-pointed star to its right.

Ratio 2:3 · current design adopted 1936

Türkiye

Field and colours only. Not shown: a white crescent and five-pointed star.

The crescent and star are not, historically, Islamic symbols — the crescent was a device of Byzantium adopted by the Ottomans, and its association with Islam spread outward from the Ottoman flag rather than the other way round. Turkish law specifies the geometry exactly: the crescent's outer circle has a diameter half the flag's height, the star sits a specific distance from it, and the star has one point aligned with the crescent's axis rather than pointing straight up. Most reproductions get the star's rotation wrong. The 1936 flag law replaced a design in use since 1844.

Flags it gets confused with

Flag	How to tell them apart
Tunisia	Tunisia places its crescent and star inside a white disc at the centre of the red field.

What the colours mean

Flag laws usually specify a Pantone chip, a CMYK mix or just a colour name. Converting any of those to sRGB is lossy, which is why published hex values disagree.

The symbols on it

What	What it stands for
Crescent and star	An Ottoman emblem, in use long before it became associated with Islam generally

Ratio: 2:3
Current design adopted: 1936
Colours: red, white

Common questions

What does the flag of Türkiye look like?: A red field with a white crescent and a white five-pointed star to its right.
What do the colours of the Türkiye flag mean?: Red: the field; traditionally the blood of the fallen. White: the crescent and star.
How do you tell the Türkiye flag from the Tunisia one?: Tunisia places its crescent and star inside a white disc at the centre of the red field.
When was the Türkiye flag adopted?: The current design dates from 1936, and its official ratio is 2:3.

Türkiye Capital, area, population and currency
The flag of Tunisia Routinely mistaken for this one
Every flag with red in it
The flag of United States Ratio 10:19
The flag of United Kingdom Ratio 1:2
The flag of Canada Ratio 1:2
The flag of France Ratio 2:3
The flag of China Ratio 2:3
The flag of Germany Ratio 3:5
The flag of Russia Ratio 2:3
The flag of Italy Ratio 2:3

Sources

Official vendor product documentation — At One Place

How these figures are compiled and checked