How many Heavens are there in Buddhism

In Mahayana Buddhism they are listed as follows from lowest to highest.

Kāmadhātu
1. Caturmahārājakāyika
2. Trāyastriṃśa
3. Yāma
4. Tushita
5. Nirmāṇarataya
6. Parinirmitvashavartin

Rūpadhātu
7. Brahmakāyika
8. Brahmapurohita
9. Mahābrahmaṇa
10. Parīttābha
11. Apramāṇābha
12. Ābhāsvara
13. Parīttaśubha
14. Apramāṇaśubha
15. Śubhakṛtsna
16. Anabhraka
17. Puṇyaprasava
18. Bṛhatphala
19. Abṛha
20. Atapa
21. Sudṛśa
22. Sudarśa
23. Akanishtha
sometimes Sukhāvatī is placed here too

Arūpadhātu
1. Infinite Space
2. Infinite Consciousness
3. Nothing Whatsoever
4. Neither Existence Nor Non-existence (Being the highest possible state in worldly existence, this fourth sphere is also called the Peak of Existence)

Source

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