Difference between 2nd jab and booster

[Mumma331]

Hi All

This might seem a daft question, but does anyone know if there is a difference between the second dose and the booster?

Is the dose amount the same and what’s actually inside?

If anyone knows I would be most grateful!

It’s exactly the same unless you have Moderna as the booster, which is half the previous dose as that’s what works for that one.