PHP and regexp to accept only Greek characters in form

The other answers here didn't work for me. Greek Unicode characters are included in the following two blocks

• Greek and Coptic U+0370 to U+03FF (normal Greek letters)
• Greek Extended U+1F00 to U+1FFF (Greek letters with diacritics)

The following regex matches whole Greek words:

[\u0370-\u03ff\u1f00-\u1fff]+

I will let the reader translate that to whichever programming language format they may be using.

See also

• Unicode charts

To elaborate on leo pal's answer, an even more complete regex, which would accept even capital accented Greek characters, would be the following:

/^[α-ωΑ-ΩίϊΐόάέύϋΰήώΊΪΌΆΈΎΫΉΏ\s]+$/

With this, you get:

• α-ω - lowercase letters
• Α-Ω - uppercase letters
• ίϊΐόάέύϋΰήώ - lowercase letters with all (modern) diacritics
• ΊΪΌΆΈΎΫΉΏ - uppercase letters with all (modern) diacritics
• \s - any whitespace character

Note: The above does not take into account ancient Greek diacritics (ᾶ, ἀ, etc.).

Full letters solution, with accented letters:

/^[A-Za-zΑ-Ωα-ωίϊΐόάέύϋΰήώ]+$/

I'm not too current on the Greek alphabet, but if you wanted to do this with the Roman alphabet, you would do this:

/^[a-zA-Z\s]*$/

So to do this with Greek, you replace a and z with the first and last letters of the Greek alphabet. If I remember right, those are α and ω. So the code would be:

/^[α-ωΑ-Ω\s]*$/