Can chunked size be calculated automatically?

[bilogic]

I have 2 problems:

A. Having to figure out what chunk size to use when coding (instead of discovery at/near runtime)
B. After figuring out, it still does not work, I have to reduce my chunk size further by about 2000 bytes

1. On Nginx + PHP FPM, all using default values, Nginx has 1M for client_max_body_size
2. However, I have to reduce my chunk size by ~2000 bytes depending on the length of the filename or face 413
3. So, what are we doing is to set client_max_body_size as 2M and upload_max_filesize as 1M
4. Would be great if there is a way to line up client_max_body_size and PHP's upload_max_filesize, i.e. set 1M for both and it works
5. Then a piece of code would work seamlessly across all servers

[bilogic]

1. I dug further and believe I found a bug, probably an issue in JS
2. In PHP, the value is set at 2MiB, i.e. 2097152
3. But using Chrome to inspect one of the 413 errors, the Content-Length was 2097997
4. JS should control its payload to be under or maximum of 2097152