Trimvale Not affiliated with any print or design platform
Trimvale

KDP trim size does not match the PDF

The error gives two sizes: the trim size you chose and the size of your pages. Drop the PDF to see every page size next to the size it must be.

The finished page size after the printer cuts the book.
Sets the inside margin. Filled in from your file.
Bleed
Bleed is artwork that runs 0.125 in past the cut line, so no white edge shows. Choose it only if pictures or colour touch the page edge.
If the pages come out cropped wrongly
Exports with crop marks are larger than the book page. Automatic uses the trim box stored in the file, or the centre when there is none.

Your PDF never leaves your browser.It is read and rebuilt on this device. Nothing is uploaded.

even pageodd pageinside margin 0.375 in each side0.25 intrim 6 x 9 in
odd page (right-hand)inside margin 0.375 intrim 6 x 9 in
6 x 9 in · 120 pages · inside 0.375 in · other margins 0.25 in

Read the two numbers

The message looks like this (wording as quoted in the Vellum help pages): "You chose 5 by 8 trim size but your interior was submitted at 5.12 by 8.25." The second pair is your PDF's page size, rounded to two decimals.

Your pages areLikely causeWhat to do
+0.125 in wide, +0.25 in tallA bleed-size file uploaded with Bleed offTurn Bleed on in the book setup, or fix to No bleed
About 0.25 to 0.5 in larger both waysCrop marks, or bleed on all four sidesCrop to the trim area
8.5 x 11 or 8.27 x 11.69 inDesign made at Letter or A4Remake at the trim size, or scale (text shrinks)
Different on some pagesPages from different designsSet every page to one size

Valid page sizes for every US paperback trim size

Trim size (no bleed)Page size with bleedNo bleed, mmWith bleed, mm
5 x 8 in5.125 x 8.25 in127 x 203.2 mm130.2 x 209.6 mm
5.06 x 7.81 in5.185 x 8.06 in128.5 x 198.4 mm131.7 x 204.7 mm
5.25 x 8 in5.375 x 8.25 in133.4 x 203.2 mm136.5 x 209.6 mm
5.5 x 8.5 in5.625 x 8.75 in139.7 x 215.9 mm142.9 x 222.3 mm
6 x 9 in6.125 x 9.25 in152.4 x 228.6 mm155.6 x 235 mm
6.14 x 9.21 in6.265 x 9.46 in156 x 233.9 mm159.1 x 240.3 mm
6.69 x 9.61 in6.815 x 9.86 in169.9 x 244.1 mm173.1 x 250.4 mm
7 x 10 in7.125 x 10.25 in177.8 x 254 mm181 x 260.3 mm
7.44 x 9.69 in7.565 x 9.94 in189 x 246.1 mm192.2 x 252.5 mm
7.5 x 9.25 in7.625 x 9.5 in190.5 x 235 mm193.7 x 241.3 mm
8 x 10 in8.125 x 10.25 in203.2 x 254 mm206.4 x 260.3 mm
8.25 x 6 in8.375 x 6.25 in209.6 x 152.4 mm212.7 x 158.8 mm
8.25 x 8.25 in8.375 x 8.5 in209.6 x 209.6 mm212.7 x 215.9 mm
8.5 x 8.5 in8.625 x 8.75 in215.9 x 215.9 mm219.1 x 222.3 mm
8.5 x 11 in8.625 x 11.25 in215.9 x 279.4 mm219.1 x 285.8 mm
8.27 x 11.69 in8.395 x 11.94 in210.1 x 296.9 mm213.2 x 303.3 mm

Source: KDP help, Set Trim Size, Bleed, and Margins. Read on 10 November 2026.

With bleed the page is 0.125 in wider and 0.25 in taller than the trim size. The extra width is on the outside edge only, never at the spine. The millimetre columns are converted here (1 in = 25.4 mm).

Scaling a Letter or A4 page down to a small trim size shrinks the text with it. KDP states a minimum font size of 7 points. The report shows the scale used and the smallest text it leaves.

Questions

My file is 6.125 x 9.25 and I chose 6 x 9. Is the file wrong?

No, that is the correct size for a 6 x 9 in book with bleed. Turn Bleed on in the print options of the book setup and upload it again.

How close does the size need to be?

KDP does not publish a tolerance. The error reports sizes to two decimals, so this tool treats anything within 0.01 in as a match and sets the corrected file to the exact size.

More answers

Did it work for your file?