Key takeaway: If you want one answer: start with an A5 journal. It is the best default size for most people – enough room to write, still easy to carry. Use the chart below only if you already know you need more pocketability (A6) or more desk space (A4/B5).
Journal sizes are the page dimensions of a notebook, usually listed in millimeters and inches. If you are comparing A4, A5, A6, B5, B6, or pocket formats, the chart below is the quick answer. After that, I will share what I have learned from keeping more than one size at once.
If you want one safe first journal size, start with A5 – enough room to write, still easy to carry – then use the chart below to compare the rest.
Journal Sizes Chart (mm and inches)
These are the standard paper sizes most journals are labeled against – the A sizes are ISO, and Japanese makers use the slightly different JIS B5. Width is listed first, then height.
| Size | Millimeters | Inches | Rough feel |
|---|---|---|---|
| A4 | 210 x 297 mm | 8.3 x 11.7 in | Desk-size; close to US Letter |
| B5 (ISO) | 176 x 250 mm | 6.9 x 9.8 in | Large writing space without full A4 bulk |
| B5 (JIS) | 182 x 257 mm | 7.2 x 10.1 in | Slightly taller Japanese B5 used by many planners |
| A5 | 148 x 210 mm | 5.8 x 8.3 in | Most common journaling size; bag-friendly |
| B6 | 125 x 176 mm | 4.9 x 6.9 in | Compact daily carry with more room than A6 |
| A6 | 105 x 148 mm | 4.1 x 5.8 in | True pocket size for short notes |
A few popular brands use house sizes that sit near these standards rather than matching them exactly:
| Common label | Typical dimensions | Closest standard |
|---|---|---|
| Pocket (Field Notes style) | 90 x 140 mm / 3.5 x 5.5 in | Between A7 and A6 |
| Moleskine Pocket | 90 x 140 mm / 3.5 x 5.5 in | |
| Moleskine Large | 130 x 210 mm / 5.1 x 8.3 in | Near A5, a bit narrower |
| Leuchtturm1917 Pocket | 90 x 150 mm / 3.5 x 5.9 in | Near A6 |
| Leuchtturm1917 A5 / Medium | 145 x 210 mm / 5.7 x 8.3 in | Near A5 |
| Composition book | 191 x 248 mm / 7.5 x 9.75 in | Near B5 |
If a cover or refill has to fit exactly, trust the millimeter measurement on the product page over the letter on the front. For a deeper brand-by-brand chart, Galen Leather keeps a useful notebook sizes guide.
Which Journal Size Fits Which Habit?
- A6 or pocket: quick lists, one-sentence days, and a notebook that has to disappear into a bag or jacket.
- B6: a daily habit that needs a little room but still travels well.
- A5: the default for most people. Enough space for a morning page or a simple daily template without feeling like homework.
- B5: longer thinking, project notes, and desk use when you want more air on the page.
- A4: planning spreads, sketches, or any practice that benefits from a full sheet.
If you are still deciding how the page itself should work, pair the size choice with a simple structure from my guide to structuring a journal, or start from a ready layout in the free journal templates library.
My Experience with Different Journal Sizes
For those of you who keep or want to keep a physical journal, a common question I get is what size is best to use. Having heard that question from a handful of you, I put my answer into this post, starting with my own experience.
Journaling began with my intrinsic desire to write things down so I could act on them instead of letting them loop in my head. I began by writing on whatever was available – Post-it notes, lined paper, printer paper – and eventually moved to more structured daily journals.
Today, I keep journals of different sizes for different purposes. My main journal (black) is organized by date so I can plan each day; the big journal (blue) is for free-form thinking about larger ideas; and the ring-bound journal is my gym journal, where I track exercise details.
I encourage you to focus on writing down whatever occupies your mind, using whatever you have available, and then going back to adjust the types of journals you use. This process may repeat itself every few years. Over time, you will realize that journaling is not about only one journal size or type.
How to Choose a Journal Size
After journaling for a week or so, review your entries and ask one practical question: did the page give you enough room to write freely and clearly? When I reviewed my own entries, I realized I did not have enough space for larger thoughts about a project, so I started using the large blue journal you see above.
A useful rule of thumb:
- If you abandon pages because they feel huge, go smaller.
- If you run out of space before the thought is finished, go larger.
- If you leave the journal at home because it is awkward to carry, prioritize the size you will actually bring with you.
Do not make it more complicated than that. Brand, paper quality, dates, look, and feel matter much less than your willingness to write and articulate yourself, which is by far the most important factor.
If you are just getting started, the beginner’s guide to journaling walks through the first habits before you worry about the perfect notebook.
7 comments On What Size Journal Should I Keep? (A4, A5, A6 Chart)
Good experience
Completed!! Looking forward to go ahead.thankyou so much sir for such valuable content.
Good
Great Effort thankyou for your lecture
Hi I have started a daily journal but have found i do like more so i have an a3 book with which i draw, paint and stick things in i guess its more a inspiration visual journal with quotes and things that stick out in my self developement courses i am doing and motivational daily things I listen to and watch from a wide range of speakers. I am loving it and the more I do the more things open up to me.
Nice! Thanks for sharing your example, Raelene. It is a perfect example of having a journal that is flexible enough to fit your creative way of expression – writing, draw, paint, stick things etc.
Good point about the size. I just write on a big paper so I always have more space to write.