Chart showing written tone marks and how they are pronounced with MIDDLE CLASS INITIAL CONSONANTS.   In the second chart below (scroll down), you can listen to examples of all the combinations of written tone marks and the three initial consonant classes.

The Thai language has five spoken tones: MID, LOW, FALLING HIGH, RISING.  But there are only four written tone marks, as shown here.  The written tone mark appears above the syllable-initial consonant or the second consonant in an initial consonant cluster. 

The relationship between spoken tones and written tone marks is shown is seen in the additional chart showing the relationship between spoken tones and intial consonants, syllable type (smooth vs. checked), vowel length, and written tone marks. 

9y;vpjk': Click at any word to listen to the sound.