The table below shows the structures of the 7 thaalams. The number of aksharams in the Laghu is decided by the Jaathi. Each thaalam has a normal ('default') jaathi and when jaathi is not mentioned the normal jaathi is implied. For jaathis other than the normal jaathi of a thaalam the jaathi has to be mentioned.
[Laghu - beat followed by counts to complete number of aksharams of the jaathi]
[Dhrutham - beat and wave = 2 aksharams. Anudhrutham - beat = 1 aksharam]
| Thaalam Name | Thaalam Structure | Normal Jaathi | Aksharams for normal Jaathi |
| Dhruva | Laghu, Dhrutham, Laghu, Laghu | Chathusra | 4+2+4+4 = 14 |
| Matya | Laghu, Dhrutham, Laghu | Chathusra | 4+2+4 = 10 |
| Roopaka | Dhrutham, Laghu | Chathusra | 2+4 = 6 |
| Jampa | Laghu, Anudhrutham, Dhrutham | Misra | 7+1+2 = 10 |
| Thriputa | Laghu, Dhrutham, Dhrutham | Thisra | 3+2+2 = 7 |
| Ata | Laghu, Laghu, Dhrutham, Dhrutham | Khanda | 5+5+2+2 = 14 |
| Eka | Laghu | Chathusra | 4 |
Thus Ata Thaalam without mention of jaathi would mean Khanda Jaathi Ata thaalam; for other jaathis of Ata thaalam we have to mention the jaathi. Aadhi thaalam is actually Chathusra Jaathi Thriputa (Laghu 4, Dhrutham 2, Dhrutham 2 = 8 - not the default for Thriputa). The order in which the thaalams are mentioned above is used historically ( ex- for Alankaarams in beginner' s lessons). The Alankaarams use the default jaathi's and so we do not find Aadhi thaalam in them. Dheekshithar composed the first 7 Navagraha Krithis starting from Sooryamoorthe (on Sun) in these seven thaalams and in that order.