Your Filofax is whatever you need it to be. If you just want a notebook with movable and replaceable pages, it can be that. If you want a flexible diary, with different page layouts for different purposes, it can be that. If you need a lot of reference notes and diagrams with you all the time, it can be that too. It can be all of those things, if that's what you need, or anything else.
With a range of sizes available, you can have a small Pocket Filofax in your pocket, or a big A5 Filofax in your bag - or both! It's the classic answer to the need for a more flexible type of notebook, and all the things that made it a great organisation tool in the 1920s, and the choice of the upwardly-mobile in the 80s, still make it the perfect answer now for those who still appreciate the analogue ways of organising and taking notes.
If you're a fan of Filofax organisers, and similar binders, we should start by recommending Philofaxy - a wonderful blog full of information about these flexible tools. You're bound to find some great ideas from other Filofax lovers there. The FAQ includes a lot of useful reference information, and there are even diary layouts to download for those who want to print their own!
There are lots of different Filofax organisers, in a variety of different styles - you just need to choose the style that suits you. There are beautiful leather binders that will age nicely, showing signs of use, but just looking better as they do. For vegans, who don't want to use leather, there are still plenty of lovely options, using PVC and other materials, to make hard-wearing binders that still look great. Leather tends to be used for the higher-priced binders, giving another good reason to choose one made from other materials! If you love the look and feel of real leather, though, it's a worthy investment for something you're going to use many times a day.
Most have some sort of closure to keep things together - press-studs are the classic Filofax closure, but some have elastic closures, and some have none at all. If you want quick access to the contents, and you're going to carry it in such a way that it's not likely to open accidentally, having no closure might be an advantage for you, but most people would probably prefer it stay shut on its own.
Lastly, the cover materials vary in how stiff they are. While most will be perfectly fine for holding and writing in, some of the softest covers will allow the contents to flex, especially in the larger sizes, making them better suited for use when you can put them on a table or desk.
Filofax make their organisers in a wide range of sizes, to suit all sorts of uses. From the smallest to the largest, their current range consists of:
Pocket: a bit smaller than the classic Personal size, Pocket binders are small enough to go in a large pocket, but can still be quite bulky. The pages are small, of course, but only a little smaller than a standard index card, so still big enough for a few notes. Many of these binders are designed to double-up as a big, chunky wallet, with card slots and a 'wallet' compartment across the whole cover. Six rings, evenly spaced (19mm apart).
Personal: the classic Filofax size. Too big for most pockets, though you might be able to fit it in a large coat pocket. Because it's the classic size, it has the widest choice for inserts. Big enough to have enough space for most uses, while still being reasonably easy to carry everywhere, as long as you have a bag or big pockets! Six rings, in two groups of three (19mm apart in the groups, wider space between).
A5: a big organiser to carry, but gives you a lot of space to work in. Better suited to those who have bigger needs, or spend most of their time at a desk or table, but would fit comfortably in most bags. A wide range of refills is available. Six rings, in two groups of three (19mm apart in the groups, wider space between).
A4: we don't currently stock any of the A4 binders, and there aren't many available. Limited range of refills. A very big organiser to carry, for those who really need the space! The A4 Filofax binders use the standard European 4-hole layout, making them compatible with most 4-hole punched paper, and also meaning the A4 refills can be used with other 4-ring binders. Will also work with 2-ring binders, but the pages won't be held in place as well - perfect for cost-effective archiving, though!