Something that is never mentioned for these posts, is the value of money, or PPP. The value of 1 USD varies from country to country. In the EU, you might be able to get a tiny 2 cm piece of chocolate, while in Africa you can actually buy proper food. This applies for defence spending as well.

Furthermore, there is a lot of stuff that is not included in the e.g. Chinese defense budget, that IS however included in the US one (but stuff that China nonetheless spends money on). This should be corrected before one can make a proper comparison.

If one applies a modifier accounting for the PPP difference, then China is suddenly at $465 to $514 billion.

If one applies a modifier for both PPP and wage differences, then the equivalent budget would be around $882 to $988 billion.

Short video that goes over this, if one might be curious: https://www.youtube.com/watch?v=o39SFpfr6E8

But well, do note. It's China. So numbers are only guesstimates.