A complete guide to paper and notebook sizes

Choosing a new notebook is exciting for stationery lovers. From browsing the paper thickness and quality to selecting a cool cover design, there’s nothing quite like finding a notebook that perfectly meets your needs and style. 

Of course, the right notebook size for your tasks, bag, and lifestyle is a key factor to consider. You might need a large option to take long notes, or something smaller to quickly jot down work tasks or journal your thoughts. 

However you plan to use your notebook, the size can have a big impact. Make a confident decision with our breakdown of notebook and paper sizes to make the perfect pick.

Why notebook sizes matter 

The practicality and usability of a notebook greatly depend on its size. A larger notebook provides more space for writing detailed notes, but you need a bigger bag to carry it. If you’re only making short notes, a large notebook can become an unnecessary inconvenience. 

Smaller notebooks are lightweight and portable, fitting easily into most bags. They’re perfect for jotting down notes on the go or simply listing ideas that come to mind. The trade-off, however, is limited writing room, which won’t work for longer creative sessions. 

Different uses naturally suit different notebook sizes. You need to determine exactly what you’ll use the notebook for and understand the various paper sizes to select a special one for writing.

Understanding paper size standards 

In the UK, paper and notebook sizes are based on the ISO 216 paper standard.  This is the standard global system, excluding North America where a system using letter sizing is more common. The paper standard ensures consistency across products, so you know an A5 writing pad from one brand will be the same size as another. 

Under the ISO system, each paper size is half the area of the previous sheet when folded to its shorter side. For example, an A4 sheet of paper folds into an A5 size, which can then be folded into an A6. This proportional system  makes it easy to scale documents either up or down without changing the layout or ratio. 

A-series vs B-series paper sizes 

Most people recognise the A-series paper sizes, which include the typical A4 and A5 sizes. If you’re looking for a notebook, these are the most commonly available options. 

The B-series is less popular, yet still a recognisable size across planners, books, and notebooks. From this series, you’re most likely to recognise the B5, which sits between A4 and A5 in size, offering a middle ground between writing space and portability.

While the A-series sizes are based on halving paper sizes, the B-series sizes use a different calculation, a geometric mean, to land on a middle point between two A-sizes. This makes them feel more spacious than their counterparts and enables flexible uses.   

The most common notebook sizes 

Most notebook sizes come in four options: A4, A5, A6, and B5. Each one serves different purposes depending on how (and where) they’re used.

A4 size 

The most recognisable of the A-sizes, an A4 sheet of paper measures 210 x 297 mm, offering ample writing space per page within a notebook. They’re particularly handy for long-form notes and drawing diagrams,  making them popular with students for lectures and revision notes, as well as creative writers for plot mapping. 

A5 size

A5 measures 148 x 210 mm and is exactly half the size of A4. Thanks to its balance of portability and usability, it’s one of the most popular notebook sizes. 

Many writers reach for an A5 notebook for journalling or quickly putting ideas down on paper. It’s also a great size for the office, where you can use it in meetings or to plan your next task.

A6 size 

The A6-size notebook measures 105 x 148 mm and  is the smallest of the most commonly available options. It’s a compact, pocket-friendly size that’s great for making quick notes on the go. 

While popular, the A6 does have its limitations. It’s usually reserved for list-making, and likely isn’t suitable as a primary writing pad.

B5 size 

At 176 x 250 mm, a B5 notebook can serve as a wonderful compromise or alternative to an A4 or A5. It’s much easier to take with you on the go than an A4-sized notebook and still offers enough writing space to make large, detailed notes. 

Which notebook size is right for you? 

The two notebook sizes you’re most likely to come across on the shelves are A4 and A5. If you’re choosing between these two, you’re essentially considering whether you value space on the page or space in your bag more.

Keep in mind the notebook will have to fit alongside your wallet, phone, everyday carry pen, packed lunch, and other essentials when working out the best size for you. 

Note-taking 

Consider how many notes you need to make and how long each topic will be. Are you plotting large storylines or making notes from your lectures and seminars to digest later for exams and essays? 

Longer and more detailed notes warrant a larger A4 notebook size. While you may need a bigger bag for it to fit, a notebook of this size gives you more room to get everything you need down on the page. 

Journalling 

Diary writing and journalling, while often detailed, don’t usually need as much space on a singular page as they’re not broken down by topic. An A5-size notebook is the most common choice. 

This type of writing typically happens in quieter moments, whether at home, while taking lunch, or travelling, and is usually personal. The smaller A5 size can easily slip into a bag or rest on a bedside table, hiding it away from prying eyes.  

Sketching 

For sketching, a B5 is recommended. It has more space than an A5, ideal for large, detailed drawings, yet is more compact than an A4, so it’s easier to take with you on the go. Of course, if you draw on a smaller scale, an A6 could work well too. It all comes down to the scale you need. 

Find the notebook for you 

Now you have a good understanding of the most common notebook sizes and what others typically use them for, you can more confidently choose a size that best suits your needs. 

Explore the wide selection of sleek notepads in various sizes from The Pen Company. We also boast a range of luxury journals in an array of intricate designs. There’s a style for every writer at The Pen Company.