The Types of Office Chair Armrests
Typically, office chairs do come with armrests. There are some models that are completely void of armrests, and some that can optionally be built onto your chosen office chair but generally they are a main feature.
But not all armrests are the same.
Fixed armrests are as the name implies. They are in a fixed position and cannot be adjusted. These are typically found on cheaper-end models of office chairs. They office good support for your forearms, leading to less stress on your neck and shoulders, but they are not a 'one size fits all'.
Some fixed arms may be in a good position for you on one model, while on another they may be a hindrance. Fixed armrests are normally designed in a T-shape or as a 'loop'.
Folding armrests are useful for when you require to quickly switch between using and not using armrests which typically coincides with the type of work you're doing.
Folding armrests generally only have two available positions. 'Up', where the armrest is folded up vertically, out of the way - and 'down' where the armrest is folded 90 degrees to a horizontal position.
The height and width of these armrests cannot be adjusted so you will be stuck with it's default horizontal position should you choose to use the armrest.
Adjustable armrests are the cream of the crop. The crème de la crème. These of course are found on higher-end office chair models.
While they don't all sport the exact same features, they do generally have a combination of height, width and pivot adjustments to allow you to get the very best position tailored to you and your desk.