Woven wraps are available in a number of different sizes / lengths. This can be a bit confusing, especially to a new user who may not be sure which length they would prefer.
Some wrap brands have sizes in numbers - eg, size 2, 3, 4, 5, 6, 7. Others, refer to their sizes by the actual length: eg: 4.2 mtrs, 4.6 mtrs. These generally correspond to 'numbered' size in other brands. Some brands only offer longer lengths, others, a full range of lengths. On this site you will find a list of what sizes are available for each brand on the collection page for each brand. To give a guide though:
Size 1: 2.2 mtrs (this is very rarely available)
Size 2: 2.6 mtrs
Size 3: 3.2 mtrs
Size 4: 3.6 mtrs
Size 5: 4.2 mtrs
Size 6: 4.6 mtrs
Size 7: 5.4 mtrs
But what does all this mean?
I class wraps into three broad categories, based on the carries that can be done with them. A petite person would use the shortest wrap in that category, an average wearer the medium size, and a larger wearer would use the longest size. There is some overlap between the sizes and some people may find that they can do a carry in a shorter wrap than listed, or that they prefer a longer wrap.
I've never wrapped before, what do I choose?
Babywearing educators differ in their opinions on which length wrap is the best to learn with. Some feel that long wraps are the easiest to learn with - multilayered carries are more forgiving and require less precise wrapping than single layered carries often used in shorter wraps, and in the case of front carries they are more usually 'poppable' (which means that they can be mostly pre-tied before putting the baby in). Others feel that shorter wraps are less overwhelming to a new wearer. If you've used a stretchy wrap (such a Hug-A-Bub or Sleepy Wrap), you might find a longer wrap preferable as you can do many of the same carries.
Lifestyle and the phase your baby is in often plays a part - wearers who have older babies or spend a lot of time wrapping outdoors might prefer shorties as they are quick for up and down carries, fold up small to pop into a bag, and don't drag on the ground when wrapping. If you have a baby who is wriggly, or a leaner or leg straightener, you might prefer carries that use a longer wrap as there are more layers for support. If possible, find a local babywearing group or sling library and try out a few sizes before you buy.