Chain Question

[AyBee]

Single-speed chains appear to come in lengths of 112 links - how do I work out whether this will be enough? The plan is to change the chain along with the front ring so I end up with 48x16 rather than 42x16 but I have no idea whether one chain will be enough or whether I have to buy one plus a bit?

[HardWorkers]

Am I missing something? Surely it's just existing chain length + 3 inner and 3 outer links.

Anyway, that aside I've always had to cut new single speed chains down and I run 48/18 or 48/20.

[AyBee]

Didn't want to go through the hassle of counting the existing links if I could get an answer on here That is the back up option.