The most common journal sizes are A5 (148 x 210 mm, about 5.8 x 8.3 in), B5, A6 (105 x 148 mm), B6, and the two classic TN-style formats, Regular and Passport. A5 is the everyday all-rounder, A6 and Passport fit a pocket or small bag, and B5 gives you desk-sized pages without going up to A4.
Key Takeaways
- A-series sizes come from ISO 216: each size is exactly half the one above it, so A5 is half of A4 and A6 is half of A5.
- There are two different B5 sizes. ISO B5 is 176 x 250 mm, while the Japanese JIS B5 is 182 x 257 mm, according to the paper size tables.
- US Letter (8.5 x 11 in) is close to A4, not A5. Half Letter (5.5 x 8.5 in) is the US size nearest to A5.
- TN-style sizes are not part of any standard, so always compare the cover and insert measurements on the listing before you buy refills.
- A notebook sold as "A5" often has pages trimmed a few millimeters smaller than the paper standard, so check the page size, not just the label.
Notebook size chart: A, B, US and TN-style sizes side by side
Use the chart below as your master reference: it lists the international A and B sizes, the Japanese B sizes, the common US sizes and the TN-style formats in both millimeters and inches. Width comes first, then height, the way notebooks are usually measured when they stand upright.
The A and ISO B rows follow the dimensions published for ISO 216. The JIS B and US rows come from the paper size reference tables. TN-style sizes have no official standard, so those rows use the measurements listed on our own covers and inserts, which you can check on each product page.
| Size | Millimeters (W x H) | Inches (W x H) | Typical notebook use |
|---|---|---|---|
| A4 | 210 x 297 | 8.27 x 11.69 | Desk notebooks, class notes, printing |
| A5 | 148 x 210 | 5.83 x 8.27 | Daily journals, planners, bullet journals |
| A6 | 105 x 148 | 4.13 x 5.83 | Pocket journals, tri-fold covers, lists |
| A7 | 74 x 105 | 2.91 x 4.13 | Mini notebooks, memo pads |
| B5 (ISO) | 176 x 250 | 6.93 x 9.84 | Roomy journals and study notebooks |
| B5 (JIS) | 182 x 257 | 7.17 x 10.12 | Japanese-style school and planner notebooks |
| B6 (ISO) | 125 x 176 | 4.92 x 6.93 | Reading journals, compact planners |
| B6 (JIS) | 128 x 182 | 5.04 x 7.17 | Compact journals and planners |
| US Letter | 216 x 279 | 8.5 x 11 | US printer paper, binders, legal pads |
| Half Letter | 140 x 216 | 5.5 x 8.5 | US planners and discbound notebooks |
| US Legal | 216 x 356 | 8.5 x 14 | Legal pads and forms |
| Passport booklet (ID-3) | 88 x 125 | 3.46 x 4.92 | The format real passports use; the reference point for "passport" notebooks |
| TN-style Regular (our inserts) | 120 x 210 | 4.7 x 8.3 | Tall, slim travel journals |
| TN-style Passport (our cover) | 100 x 130 | 3.9 x 5.1 | Pocket travel journals |
| TN-style Pocket (our cover) | 100 x 170 | 3.9 x 6.7 | Slim notes between Passport and Regular |
A few notes on reading the chart. The passport booklet row is the ID-3 card format, which the ISO/IEC 7810 reference lists at 125 x 88 mm and describes as the format commonly used for passport booklets. The TN-style Regular row is the insert size on our refillable PU leather travel journal set, listed at 21 x 12 cm. The Passport and Pocket rows are the cover sizes listed for our crazy horse leather refillable journal cover (13 x 10 cm and 17 x 10 cm). Other makers use slightly different numbers, which is exactly why the measuring section further down matters.
How ISO 216 halving works
ISO 216 sizes work by halving: start with a sheet of one square meter, cut it in half across the long side, and each half is the next size down with exactly the same shape. That is why A5 is half of A4, A6 is half of A5, and the number goes up as the page gets smaller.
The standard behind this is ISO 216:2007, which specifies the trimmed sizes of writing paper and certain printed matter in the A and B series. According to the ISO 216 overview, the starting size A0 is designed to have an area of one square meter before rounding, and every sheet has an aspect ratio of the square root of 2 to 1 (about 1 to 1.414). The clever part of that ratio is that it survives cutting in half. Fold an A4 sheet across its long side and you get two A5 sheets that are the same shape as the original, just smaller.
Why a bigger number means a smaller page
The number after the letter tells you how many times the sheet has been halved, not how big it is. The same reference notes that the long side of each size equals the short side of the size above it, and that dimensions are rounded down to the nearest millimeter. In practice, that gives you a simple chain you can remember:
- A4 (210 x 297 mm) cut in half gives A5 (148 x 210 mm). The 210 mm short side of A4 becomes the long side of A5.
- A5 cut in half gives A6 (105 x 148 mm). The 148 mm short side of A5 becomes the long side of A6.
- A6 cut in half gives A7 (74 x 105 mm).
This also explains a handy journaling trick. Because two A6 pages make one A5 page, a folded A5 sheet makes a perfect A6 booklet, and a folded A4 sheet makes a perfect A5 signature. If you print your own inserts or templates, you never have to resize them, only fold them.
Where the B series fits
The ISO B series fills the gaps between A sizes. Each ISO B size sits between two neighboring A sizes, which is why ISO B5 (176 x 250 mm, per the ISO 216 tables) is larger than A5 but smaller than A4. If A5 feels a little cramped and A4 feels like a school binder, a B size is the step in between.
ISO B vs JIS B: why there are two B5 and two B6 sizes
There are two B5 sizes because Japan uses its own B series. JIS B5 measures 182 x 257 mm, a little larger than ISO B5 at 176 x 250 mm, and JIS B6 is 128 x 182 mm compared with ISO B6 at 125 x 176 mm. Both are sold simply as "B5" or "B6," so the label alone will not tell you which one you are getting.
The paper size reference explains that the Japanese B series is defined so that each JIS B sheet has 1.5 times the area of the matching A sheet. Do the math with the published dimensions and the gap is easy to see:
| Size | Dimensions (mm) | Page area (sq cm) | Compared with A5 |
|---|---|---|---|
| A5 | 148 x 210 | 310.8 | Baseline |
| B5 (ISO) | 176 x 250 | 440.0 | About 42% more page |
| B5 (JIS) | 182 x 257 | 467.7 | About 50% more page |
| A4 | 210 x 297 | 623.7 | Twice the page |
For most journalers the difference between the two B5 sizes is a few millimeters, which matters mainly when you are buying a cover or binder for an existing B5 notebook. A JIS B5 refill can be too tall for a cover made around ISO B5, so check the millimeter dimensions on both. If you are torn between the everyday A5 and the roomier B5, our A5 vs B5 comparison walks through the decision by use case.
US Letter vs A4 and A5: what Americans need to know
US Letter is not the same as A5. Letter measures 8.5 x 11 in (216 x 279 mm), which puts it close to A4 (210 x 297 mm), slightly wider and shorter. The US size that is closest to A5 is Half Letter, 5.5 x 8.5 in (140 x 216 mm), which is a bit narrower and a little taller than A5.
The paper size reference notes that most countries use ISO 216, while the United States and Canada mainly use Letter-based sizes. That split is why US shoppers see two families of notebooks side by side: Letter, Half Letter and Legal on one shelf, and A4, A5 and A6 on the other. Here is how the closest pairs line up:
| US size | Inches | Closest ISO size | How they differ |
|---|---|---|---|
| Letter | 8.5 x 11 | A4 (8.27 x 11.69 in) | Letter is about 0.23 in wider and 0.69 in shorter |
| Half Letter | 5.5 x 8.5 | A5 (5.83 x 8.27 in) | Half Letter is about 0.33 in narrower and 0.23 in taller |
| Legal | 8.5 x 14 | No close ISO size | Much taller than A4 |
Why does this matter in practice? Two reasons. First, printables. A printable made for Letter paper will not fill an A4 or A5 page cleanly, and the reverse is also true, so pick templates that match your notebook. Second, refills. A Half Letter insert will feel close to A5 in the hand, but a cover built tightly around A5 may not close neatly over a taller Half Letter page, or the narrower insert may slide around. When in doubt, compare millimeters.
Which notebook size to choose for each use
Pick the size by where the notebook will live and how much you write per entry. A5 suits daily journals and planners, B5 suits long-form writing and desk work, A6 and B6 suit carry-everywhere notebooks, and TN-style Regular or Passport suits travel journals and layered setups. The table below is our practical guide, based on page area and portability rather than any rule.
| Use | Good sizes | Why | Watch out for |
|---|---|---|---|
| Daily journal | A5, B6 | Room for a full entry per page without feeling empty | A5 plus a thick cover can be heavy in a small bag |
| Planner or bullet journal | A5, B5 | Weekly spreads and monthly calendars need width | A6 and Passport get cramped for weekly layouts |
| Travel journal | TN-style Regular, Passport, A6 | Slim, light, easy to hold while standing | Ticket stubs may be wider than a Passport insert |
| Sketching | A5, B5 | Bigger pages for drawing and color studies | Pair with heavier paper; see our gsm paper guide |
| Pocket notes and lists | A6, A7, Passport | Fits a jacket pocket or small purse | Little space for long thoughts |
| Meeting and study notes | B5, A4 | Wide margins and room for diagrams | Less comfortable to carry every day |
Daily journaling
For a daily journal, A5 is the safe default. One A5 page at 148 x 210 mm holds a substantial entry, the notebook still fits most tote bags, and A5 covers and inserts are easy to find. If you write short entries or want something lighter, B6 is a good step down. Our A5 dot grid and lined notebook with pen loop lists its size at 21 x 14.5 x 1.5 cm, a typical everyday A5 footprint.
Planning and bullet journaling
Planning layouts need width more than height. A weekly spread splits the page into seven columns or boxes, and on an A6 page each box gets very small. A5 is the usual starting point, and B5 gives you even more room for trackers and notes beside the calendar. If you are setting up your first planner, start with A5 dot grid pages; they work for both lists and grids.
Travel and everyday carry
For travel, think about where you will write. On a train, in a cafe or standing at a viewpoint, a slim notebook you can hold in one hand is easier than a wide one. That is the appeal of the TN-style Regular format, which keeps roughly the height of A5 but trims the width. Passport-style notebooks go smaller still. Our TN-style notebook sizes guide covers Passport, Regular, A6, B6 and A5 covers in detail.
Sketching and mixed media
For sketching, size and paper weight go together. A larger page gives you room to draw, but thin paper will cockle or show through when you add ink or paint. Look at the paper spec first, then pick the biggest size you will actually carry.
What sizes do travel journals come in?
Travel journals usually come in four sizes: TN-style Passport, TN-style Pocket, TN-style Regular, and A5, with A6 tri-fold covers as a fifth option. Our crazy horse leather travel journal, for example, is offered in Passport, Pocket, Regular and A5, and each size is listed with its packed dimensions on the product page.
The TN-style sizes are not defined by any standards body. They are conventions that grew out of refillable leather covers with elastic bands, and each maker measures slightly differently. Use the measurements on our crazy horse leather refillable cover as an example: Passport 13 x 10 cm (5.1 x 3.9 in), Pocket 17 x 10 cm (6.7 x 3.9 in) and Regular 22 x 12 cm (8.7 x 4.7 in). An A6 tri-fold cover is a different style again: it holds standard A6 loose-leaf pages, which our A6 tri-fold PU leather cover with strap lists at 10.5 x 14.8 cm.
If you are new to the format, our guide on choosing a TN-style size explains which format suits which kind of trip, and how many inserts you can layer in one cover.
Real sizes of the notebooks and covers we sell
Labels are a starting point, but the real measurements on the listing are what decide whether a notebook fits your bag or cover. Here are the sizes listed on several PageFrond notebooks and covers, so you can compare them with the standard sizes above.
| Product | Format on the listing | Listed size | Notes |
|---|---|---|---|
| A5 dot grid and lined notebook with pen loop | A5 | 21 x 14.5 x 1.5 cm notebook | PU cover, dot grid and lined pages, two ribbons |
| B5 soft PU leather notebook, pebble grain | B5 | 27.2 x 20.5 x 2.5 cm packed | 100 gsm white paper, thread-bound |
| Refillable travel journal set with 4 inserts | TN-style | 21 x 12 cm inner notebooks | PU cover, four 100 gsm inserts of 50 sheets each |
| Crazy horse leather refillable journal cover | Passport, Pocket, Regular | 13 x 10, 17 x 10, 22 x 12 cm | Cow leather cover, 100 gsm paper included |
| A6 tri-fold PU leather cover with strap | A6 loose-leaf | 10.5 x 14.8 cm inserts | Shell alone or with 45 inner sheets |
Notice two things. First, a packed size is not a page size. The B5 notebook's packed size includes the cover and packaging, so the pages themselves are smaller than 27.2 x 20.5 cm. Second, the A5 notebook's listed width of 14.5 cm is slightly under the 148 mm A5 standard. That is normal: many notebooks are trimmed a few millimeters inside the paper standard once the cover and binding are added. When a fit matters, compare the page size on the listing with your cover or insert, and ask us through our contact page if a listing does not show the number you need.
What fits inside what: matching covers and inserts
An insert fits a cover when it is smaller than the closed cover in both height and width and the same format family. Regular inserts go in Regular covers, Passport in Passport, and A6 loose-leaf pages in A6 binders. Mixing families rarely works well even when the numbers look close.
Use this quick matching guide, built from the sizes in our listings and the standard dimensions above:
| Cover type | Takes | Will not fit well |
|---|---|---|
| TN-style Passport cover | Passport inserts | A6 pages (148 mm tall is taller than a 13 cm cover) |
| TN-style Pocket cover | Pocket inserts | Regular inserts (too tall) |
| TN-style Regular cover | Regular inserts (about 21 x 11 to 12 cm) | A5 notebooks (148 mm is wider than a 12 cm cover) |
| A6 tri-fold or ring binder | A6 loose-leaf pages, 10.5 x 14.8 cm | Passport inserts with no punched holes |
| A5 cover or binder | A5 notebooks and inserts | Half Letter pages in a tight cover (taller than A5) |
The examples in the right-hand column come straight from the numbers. An A6 page is 148 mm tall per the ISO 216 tables, so it cannot sit inside a 13 cm Passport cover. An A5 page is 148 mm wide, so it cannot close inside a Regular cover listed at 12 cm wide. You can browse all of our covers, inserts and refill-ready shells in the notebook covers and inserts collection.
How to measure a cover vs an insert
Measure a cover closed, from edge to edge, and measure an insert closed, from the spine to the outer edge. The insert should be slightly smaller than the cover in both directions so the cover protects the page edges. Follow these steps and you will rarely buy a refill that does not fit:
- Close the cover and lay it flat. Measure the height along the spine and the width from the spine to the front edge. Write both numbers down in millimeters.
- Measure the insert you already own, closed. Height along its spine, width from spine to edge. If you have no insert, use the insert size stated on the listing.
- Subtract. Cover height minus insert height, and cover width minus insert width. Both results should be positive. A small margin keeps the page corners from poking out; a very large margin lets the insert slide around.
- Check the binding style. TN-style covers hold booklets with elastic bands, ring binders need punched pages, and tri-fold shells need their specific loose-leaf format. The right size in the wrong system will not work.
- Allow for thickness. If you plan to carry several inserts, a pen and a pocket folder, the cover has to close over all of them. Check the spine width and any thickness on the listing.
- Compare against the listing, not the name. "Regular," "Standard" and "Wide" can mean slightly different sizes from different makers. The millimeter numbers are the only reliable comparison.
A tip for measuring: use a ruler marked in millimeters rather than a tape measure. A difference of 5 mm is easy to miss in inches but is exactly the kind of gap that decides whether a cover closes neatly.
Three questions that settle the size decision
If you are stuck between two sizes, answer three questions in order: where the notebook will travel, how much you write in one sitting, and whether you want to refill it. Most people find that the first answer rules out half the options and the second picks the winner.
1. Where will it travel?
Measure the bag, pocket or desk drawer where the notebook will spend most of its time. A notebook that stays at home can be B5 or A4 without any downside. A notebook that goes to work every day should fit your work bag with room to spare, which usually means A5 or smaller. A notebook that rides in a jacket pocket needs to be A6, Passport or similar. Remember that the cover adds to the page size, so measure the notebook as a whole, not just the paper.
2. How much do you write at once?
Think about a typical entry. If you jot a few lines, a short list or a quick sketch, small pages feel satisfying because you fill them. If you write a page or more, or you like to plan a whole week on one spread, a small page will push you to turn pages constantly and the notebook fills up fast. Short entries point to A6, B6 or Passport; long entries and planning spreads point to A5 or B5.
3. Do you want to refill it?
If you like the idea of keeping one cover for years and swapping the pages, pick a refillable format first and let it decide the size. TN-style covers take slim booklet inserts, A6 and A5 binders take loose-leaf pages, and bound notebooks are replaced as a whole when they are full. A refillable cover is also the easiest way to keep separate inserts for a journal, a planner and a sketchbook in one place.
Once you have answered all three, check the chart at the top of this guide for the exact measurements, then compare them with the listing of the notebook or cover you have in mind.
Size is only half the story: pages, paper and binding
Two notebooks of the same size can feel completely different because of paper weight, page count and binding. When you compare notebooks, read three more specs after the size: the paper weight in gsm, the number of sheets or pages, and whether the binding lets the notebook open flat.
- Paper weight. Paper weight is measured in grams per square meter (gsm). Our guide to gsm paper explains what different weights handle and how to run a quick bleed test at home.
- Sheets vs pages. A sheet has two sides, so "100 sheets" means 200 writable pages. Listings use both terms, so check which one you are reading.
- Binding. Thread-sewn and lay-flat bindings are easier to write in close to the spine, which matters more on smaller pages where every millimeter counts. Glued bindings can be stiffer.
- Cover. A thick leather or hardcover adds a few millimeters to the outside dimensions, so the notebook will always be a little larger than its page size.
If you are still deciding on size, keep it simple: choose A5 for your first journal, try B5 if you find yourself running out of space, and switch to a TN-style or A6 cover when you want something you will carry every day.
Frequently asked questions
What's the most common notebook size?
For journals and planners, A5 is the usual starting point. It measures 148 x 210 mm (about 5.8 x 8.3 in) under ISO 216, which makes it big enough for a full entry and small enough to carry. In US offices and schools, Letter-size notebooks (8.5 x 11 in) are also very common.
What are the standard sizes of notebooks?
The standard notebook sizes are the ISO A series (A4, A5, A6, A7), the B series (ISO B5 and B6, plus the slightly larger Japanese JIS B5 and B6) and the US sizes Letter, Half Letter and Legal. TN-style sizes such as Regular and Passport are popular formats, but they are conventions rather than official standards.
Is 8.5 x 11 the same as A5?
No. 8.5 x 11 in is US Letter, which is close to A4 (8.27 x 11.69 in), not A5. A5 is half of A4, at about 5.83 x 8.27 in. The US size nearest to A5 is Half Letter, 5.5 x 8.5 in, which is slightly narrower and slightly taller than A5.
What are the different sizes of travel journals available?
Travel journals usually come in TN-style Passport, Pocket and Regular sizes, plus A5 and A6. Exact measurements vary by maker. Our crazy horse refillable cover, for example, lists Passport at 13 x 10 cm, Pocket at 17 x 10 cm and Regular at 22 x 12 cm, so compare the listed numbers before buying inserts.
How big is a 4x6 notebook?
A 4 x 6 inch notebook measures about 102 x 152 mm. That is very close to A6, which is 105 x 148 mm (about 4.1 x 5.8 in), so a 4 x 6 notebook is a little narrower and a little taller than A6. Either size slips easily into a jacket pocket or small bag.
Find the right size for your next journal
Now that you know how the sizes compare, the easiest next step is to browse by format. Our notebooks and planners collection includes A5 and B5 notebooks with the page sizes listed on each product, and our covers and inserts collection holds TN-style and A6 refillable options. Every listing shows the measurements you need to check fit before you order.
US orders ship for a flat $6.99 and free on orders of $79 or more, with delivery in 7 to 14 business days including 1 to 3 days to process. If you are not sure which size suits you, start with A5 from the notebooks and planners collection and build from there.
