KDP margin calculator · Free · No sign-up
KDP Margin Calculator
A KDP margin calculator gives the smallest margins Amazon KDP accepts for a paperback interior. A 300-page book needs an inside (gutter) margin of at least 0.5 in, and at least 0.25 in outside, top and bottom, or 0.375 in with bleed. The inside minimum steps up with the page count.
It also gives the page size and Word settings.
300 pages is in KDP's 151 to 300 band: inside margin at least 0.5 in. It steps up to 0.625 in at 301 pages, 1 more.
- Inside (gutter) minimum
- 0.5 in
- Outside, top, bottom minimum
- 0.25 in
- Page size to export
- 6 × 9 in
- Trim size
- 6 × 9 in
- Text block at the minimums
- 5.25 × 8.5 in
- Bleed
- none
- Gutter steps up at
- 301 pages
| Margin | KDP minimum (in) | Minimum (mm) | Comfortable (in) | Comfortable (mm) |
|---|---|---|---|---|
| Inside (gutter) | 0.5 | 12.7 | 0.8 | 20.3 |
| Outside | 0.25 | 6.4 | 0.65 | 16.5 |
| Top | 0.25 | 6.4 | 0.8 | 20.3 |
| Bottom | 0.25 | 6.4 | 0.9 | 22.9 |
| Text block, wide × high | 5.25 × 8.5 in | 4.55 × 7.3 in | ||
| Setting | Value |
|---|---|
| Paper size, width × height | 6 × 9 in |
| Multiple pages | Mirror margins |
| Top / Bottom | 0.8 / 0.9 in (comfortable), at least 0.25 in |
| Inside | 0.8 in (comfortable), at least 0.5 in |
| Outside | 0.65 in (comfortable), at least 0.25 in |
| Gutter | 0 in: the inside margin already includes it |
Inside: KDP's 151 to 300 page band gives 0.5 in, and it is the total on that side, not an amount on top of another margin. Outside, top and bottom: 0.25 in. The comfortable column is a suggestion from this page, not a KDP rule. KDP’s previewer is the final word on the file you upload.
The figures above are an example: put in your own. Worked out in this browser and kept there. Not sure of the page count yet? Estimate it with the book page count calculator.
Enter the page count, choose the trim size and say whether any image or colour reaches the edge. The inside, outside, top and bottom margins come out in inches and millimetres, with the page size to export, the text block that is left and the settings to type into Word.
The gutter is the inside margin, next to the spine. KDP sets a minimum for it that rises with the page count, from 0.375 in up to 0.875 in, and it is the whole inside margin, not an amount added to another one.
- No sign-up
- Nothing uploaded
- KDP's published figures
- Works offline
- Shows its working
Key facts
| Detail | Answer |
|---|---|
| Price | Free, no sign-up, nothing to install |
| Inside (gutter) minimum | 0.375 in to 150 pages, 0.5 to 300, 0.625 to 500, 0.75 to 700, 0.875 to 828 |
| Outside, top, bottom | At least 0.25 in without bleed, 0.375 in with bleed |
| 300 pages, 6 × 9 in, no bleed | Inside 0.5 in; text block 5.25 × 8.5 in at the minimums |
| Bleed | 0.125 in on the top, bottom and outside edges: a 6 × 9 in page becomes 6.125 × 9.25 in |
| Page counts covered | 24 to 828, KDP’s paperback range |
| Where the minimums come from | KDP’s “Set Trim Size, Bleed, and Margins” help page |
| Where your numbers are kept | This browser only |
How to find your KDP margins
Enter the book’s details, then type the figures into your layout software.
Enter the page count
Use the page count of the finished interior file, blank pages included; the book page count calculator will estimate it if the manuscript is not typeset yet.
Choose the trim size
Pick the page size you set in KDP, or enter your own width and height in inches.
Say whether there is bleed
Choose bleed only if an image or colour runs to the page edge.
Read the board
The inside minimum comes first, with the outside, top and bottom figure under it.
Check the next band
If the page count is a few pages under a step, the gutter will rise when you add them.
Set the page and margins
Copy the page size and margins into Word with mirror margins on, then check KDP’s previewer.
Who uses a KDP margin calculator
Anyone setting up the pages of a paperback for KDP, from a first novel to a workbook series.
Self-publishing authors
The margins to type into Word before the manuscript is flowed in.
Formatters
A check of a client’s file against the gutter for its final page count.
Low-content book makers
Journals and planners with a page count near a band edge, where one page changes the gutter.
Authors who got a margin warning
The figure KDP’s previewer wanted, and why the file failed.
Workbook and textbook authors
Large trims such as 8.5 × 11 in, where the text block is wide.
Anyone choosing a trim size
The text block each size leaves at the same page count; the book trim size chooser suggests the size first.
The KDP gutter by page count, and when it steps up
KDP does not ask for one inside margin. It asks for more as the book gets thicker, because a thick book opens less flat and the text nearest the spine curves away from the reader. The inside (gutter) minimum is set by the page count of the finished interior file, in five bands.
| Pages | Inside minimum (in) | Inside minimum (mm) | Outside, top, bottom (no bleed, in) |
|---|---|---|---|
| 24 to 150 | 0.375 | 9.5 | 0.25 |
| 151 to 300 | 0.5 | 12.7 | 0.25 |
| 301 to 500 | 0.625 | 15.9 | 0.25 |
| 501 to 700 | 0.75 | 19.0 | 0.25 |
| 701 to 828 | 0.875 | 22.2 | 0.25 |
The step is sharp. A book of 150 pages needs 0.375 in inside, and one of 151 needs 0.5 in, so adding a single page at the top of a band moves the gutter by 0.125 in and the text block with it. Read the table at the page count of the file you upload, not the manuscript count: a few blank pages or an added author note can cross a line. The calculator says how many pages are left before the next step.
Bleed and the page size to export
Bleed is for pages where an image or a colour runs to the edge. KDP trims 0.125 in (3.2 mm) from the top, bottom and outside edges, so a file with bleed is 0.125 in wider and 0.25 in taller than the trim size. The inside edge is bound, never cut, so it gets no bleed. A page without bleed needs only the trim size.
| Trim size | No bleed (in) | With bleed (in) |
|---|---|---|
| 5 × 8 in | 5 × 8 | 5.125 × 8.25 |
| 5.5 × 8.5 in | 5.5 × 8.5 | 5.625 × 8.75 |
| 6 × 9 in | 6 × 9 | 6.125 × 9.25 |
| 7 × 10 in | 7 × 10 | 7.125 × 10.25 |
| 8.5 × 11 in | 8.5 × 11 | 8.625 × 11.25 |
With bleed, KDP raises the outside, top and bottom minimum from 0.25 in to 0.375 in, which is the 0.25 in plus the 0.125 in bleed. The inside minimum does not change. Choose bleed only if something really touches the edge: a book of plain text does not need it, and a file made with bleed for a book set up without it, or the reverse, is a common reason for a resized page in the previewer. KDP’s help gives the figures but does not say where on the page they are measured from, so check the previewer.
What to type into Word’s Page Setup
The settings are the same in any word processor that has them; Word is shown here because it has the one control that matters, mirror margins. Without it, the left margin on every page is the same and the gutter lands on the wrong side of every second page.
- In Layout, open Page Setup and set the paper size to the width and height in the first row of the Word table above: the trim size, or the bleed size if you use bleed.
- On the Margins tab, under Multiple pages, choose Mirror margins. The left and right boxes become Inside and Outside.
- Type the Top, Bottom, Inside and Outside values. KDP’s inside figure is the whole inside margin, so leave Gutter at 0. If you type a gutter as well, Word adds it to the inside margin, which is more than KDP asked for and narrows the text.
- Export to PDF and open KDP’s previewer. Check that nothing sits in the gutter and that no warning appears.
Google Docs: we could not confirm a mirror margins or gutter setting in its Page setup. If yours has none, it has one left and one right margin for every page, so type the inside figure into both and the outside edge will be wider than it needs to be. A layout tool with facing pages, such as InDesign or Affinity Publisher, sets inside and outside directly.
Minimum margins and comfortable margins
KDP’s figures are the least it accepts, not what looks good. A text block that runs to a quarter inch from the edge is a legal book and a cramped one. No platform publishes a recommended margin, so the comfortable column is this page’s own suggestion for a 300-page book without bleed: bigger margins on a bigger page, a wider bottom than top, and an inside margin at least 0.25 in above KDP’s minimum for the band.
| Trim size | Top / bottom (in) | Inside / outside (in) | Text block (in) |
|---|---|---|---|
| 5 × 8 in | 0.75 / 0.85 | 0.75 / 0.6 | 3.65 × 6.4 |
| 5.5 × 8.5 in | 0.75 / 0.85 | 0.75 / 0.6 | 4.15 × 6.9 |
| 6 × 9 in | 0.8 / 0.9 | 0.8 / 0.65 | 4.55 × 7.3 |
| 7 × 10 in | 0.75 / 0.85 | 0.875 / 0.75 | 5.375 × 8.4 |
| 8.5 × 11 in | 0.75 / 0.85 | 0.875 / 0.75 | 6.875 × 9.4 |
These are a starting point, not a rule. A line of 45 to 75 characters is comfortable to read, and type size changes what fits, so judge the margins on a printed proof.
What this calculator does not do
This calculator applies the margin figures KDP publishes for a paperback interior. It does not replace KDP’s previewer for the file you upload.
| It does | It does not |
|---|---|
| Give the inside minimum for the page count, and say how many pages remain before it steps up | Give figures for other printers: IngramSpark and Lulu use their own, and this page does not guess them |
| Give the outside, top and bottom minimum with and without bleed | Check your file: it cannot see whether text sits inside the margins |
| Give the page size to export and the text block left at the minimums | Cover hardcovers, which may have other figures: check KDP’s hardcover help |
| Show what to type into Word’s Page Setup | Set page numbers or running heads, which must also stay inside the margins |
| Flag a page count under 24 or over 828 | Size the cover: the KDP cover size calculator does that |
This calculator, KDP's help page or a typical third-party tool
Three ways to get KDP margins, and what each leaves out.
| This calculator | KDP’s help page | A typical third-party tool | |
|---|---|---|---|
| Cost | Free, no sign-up | Free | Free, often with an email wall or ads |
| Inside margin for your page count | Yes | A table to read | Yes |
| Pages left before the gutter steps up | Yes | No | Rarely |
| Bleed page size beside the margins | Yes | In a separate section | Rarely |
| What to type into Word | Yes, with the mirror margins trap | No | Rarely |
| Millimetres | Yes | Yes | Sometimes |
| Says what is a rule and what is a suggestion | Yes | n/a | Rarely |
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Frequently asked questions
What are the margins for KDP?
For a paperback interior, the inside (gutter) margin is at least 0.375 in for 24 to 150 pages, 0.5 in for 151 to 300, 0.625 in for 301 to 500, 0.75 in for 501 to 700 and 0.875 in for 701 to 828. Outside, top and bottom are at least 0.25 in, or 0.375 in if the pages have bleed.
What is the gutter margin for KDP?
The gutter is the inside margin, next to the spine, and KDP sets a minimum that grows with the page count: 0.375 in up to 150 pages, then 0.5, 0.625, 0.75 and 0.875 in. It is the total inside margin, so do not add it on top of another inside margin.
What margins do I need for a 6x9 book on KDP?
The same rules as any other trim size: an inside margin from KDP’s table for the page count, 0.5 in for 300 pages, and at least 0.25 in outside, top and bottom (0.375 in with bleed). A 300-page 6 × 9 in book at the minimums has a text block of 5.25 × 8.5 in; most books use bigger margins.
Do KDP margins change with the page count?
Only the inside margin does. It steps up at 151, 301, 501 and 701 pages, from 0.375 in to 0.875 in. The outside, top and bottom minimums stay at 0.25 in, or 0.375 in with bleed, whatever the page count. Check the margin again whenever the page count crosses a step.
What is the difference between bleed and no bleed?
Bleed means an image or colour runs off the page edge. KDP trims 0.125 in from the top, bottom and outside, so a bleed file is 0.125 in wider and 0.25 in taller than the trim size, and the outside, top and bottom margins rise to 0.375 in. Without bleed the page is the trim size and 0.25 in is enough.
How do I set KDP margins in Word?
In Page Setup, set the paper size to the trim size, or the bleed size, choose Mirror margins under Multiple pages, then type Top, Bottom, Inside and Outside. Leave Gutter at 0 because KDP’s inside figure is the whole inside margin; a typed gutter is added on top of the inside margin.
What happens if my margins are too small on KDP?
KDP’s previewer flags text or images that fall inside its margins, and a file with the warning can be refused or may print with text near the trim or lost in the spine. Enlarge the margins to the minimums, or reflow the text, and upload again. A change can move the page count and the gutter band.
Does adding pages change the gutter I need?
Yes, when it crosses a band. Adding one page to a book of 300 takes it from the 0.5 in band to 0.625 in at 301, which narrows the text block by 0.125 in and can add pages in turn. Settle the page count, set the gutter for it, and check KDP’s previewer at the end.
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