Vellum KDP Upload: Bleed Settings Decoded

The error message reads: "The trim size I chose does not match the file I submitted." You selected 6x9. Your Vellum project is set to 6x9. Yet KDP insists the dimensions are wrong.

The problem isn't your trim size. The problem is bleed.

Vellum added extra space around your pages because something in your book touches the edge. KDP sees a PDF that's slightly larger than 6x9 and panics. The fix takes thirty seconds once you understand what's happening.

What Bleed Actually Means

Bleed is the printing industry's solution to an imperfect process. When a commercial printer cuts paper, the blade doesn't land in exactly the same spot every time. Slight variations occur. If your design stops precisely at the intended page edge, that variation might leave a thin white line along one side of your book.

The fix: extend the design past where the cut will happen. Print shops require 0.125 inches of extra content on any edge where ink should reach the boundary. After printing, the pages get trimmed. That extra eighth-inch gets cut off, and your design bleeds cleanly to the final edge.

For a 6x9 book with bleed, the actual PDF dimensions become 6.125 inches wide (adding 0.125 to the outside edge only, not the spine) and 9.25 inches tall (adding 0.125 to both top and bottom). KDP and IngramSpark both use this standard. Vellum handles the math automatically.

What Triggers Bleed in Vellum

Vellum doesn't add bleed to every project. It only adds bleed when something in your book requires it. Three features trigger bleed:

Full Page Images. If you insert a full page image that extends to the edge of the page, Vellum adds bleed to your entire PDF. This includes images used as chapter openers, section dividers, or standalone pages in a photo book.

Heading Backgrounds. When you apply a background image or color to your chapter headings and set the extent to "Full Bleed," Vellum adds the bleed region. This is common with decorative chapter openers that have imagery extending to the page edges.

Custom Backgrounds. If you use a custom background image for your pages and set it to extend beyond the safe zone to the bleed region, the entire project gets bleed added.

Notice the pattern: anything that reaches the edge of the trimmed page requires bleed. Text-only books with standard margins never trigger it. The moment you add decorative elements that touch the boundary, Vellum protects you by adding the extra space printers need.

If you're unsure whether your project uses bleed, check your exported PDF. Open it in Preview or any PDF reader and look at the page dimensions. A 6x9 book without bleed shows exactly 6 inches by 9 inches. A 6x9 book with bleed shows 6.125 by 9.25 inches.

The KDP Upload Screen

When you upload your interior file to KDP, you'll reach the Print Options section. One of the settings is "Bleed Settings" with two options: "No Bleed" and "Bleed."

Here's the rule: your selection must match your file.

If Vellum added bleed to your PDF (because you used full-bleed elements), select "Bleed" at KDP. If your Vellum project has no full-bleed elements, select "No Bleed."

The trim size error appears when these don't match. You uploaded a PDF with bleed dimensions, but told KDP to expect a no-bleed file. KDP measured your PDF, found it larger than the trim size you selected, and assumed something was wrong.

The error also mentions that your PDF is larger than expected. It might say "The submitted file is 6.125 x 9.25 but the trim size selected is 6 x 9." This is your confirmation that the file has bleed. Select "Bleed" in the Print Options, and the error disappears.

Step-by-Step Fix for the Trim Size Error

You're staring at the error. Here's exactly what to do.

First, scroll down to the Print Options section on the KDP book setup page. Look for "Bleed Settings." It probably shows "No Bleed" selected.

Second, change the selection to "Bleed."

Third, leave your trim size setting unchanged. Keep it at 6x9 (or whatever size you actually want). The trim size is the final, after-cutting size of your book. It doesn't include the bleed region.

Fourth, upload your file again or click to revalidate. The error should clear.

That's it. The entire fix is clicking one different radio button. The confusion comes from not understanding that bleed affects file dimensions without affecting trim size.

When to Use Each Setting

The decision tree is simple:

Select "No Bleed" when: Your book is text-only. You have images, but they're all inset from the page edges (photos within margins, illustrations that don't touch boundaries). Your chapter headings use Vellum's built-in styles without custom backgrounds. Ornamental breaks and scene dividers stay within the text area.

Select "Bleed" when: You have any full-page images. Your chapter headings use a background image set to full bleed. You use custom page backgrounds that extend to the edge. Any design element touches or crosses the page boundary.

Most fiction writers select "No Bleed." Your novel has text, chapter headings, maybe some ornamental breaks, but nothing touching the page edges. Most cookbooks, photo books, and heavily designed nonfiction select "Bleed."

If you're genuinely unsure, check your PDF dimensions. That tells you definitively what Vellum created.

The "Let KDP Fix It" Trap

When KDP detects a mismatch, it sometimes offers to fix the file for you. A message appears suggesting Amazon can resize your PDF to match the expected dimensions.

Never accept this offer.

KDP's automated fix doesn't understand your design. It scales your entire interior to fit the expected page size. The result: shrunken text, enormous margins, and a book that looks like it was formatted by someone who's never seen a printed page.

The text becomes tiny because it's been proportionally reduced. The margins balloon because KDP centers the shrunken content. Headers and footers move to strange positions. Images look wrong. The book becomes unprofessional and difficult to read.

The fix destroys everything Vellum did to make your book look good. It negates the $250 you paid for software that handles typography and layout properly.

If KDP shows a message about fixing your file, close that option and instead go change your bleed setting. The correct solution is always matching your upload settings to your file, not letting Amazon's automation mangle your carefully formatted interior.

The Insufficient Gutter Warning

While troubleshooting bleed, you might encounter a second error: insufficient gutter (also called insufficient inside margin). This error appears when KDP's preview tool thinks your text runs too close to the spine.

KDP requires minimum inside margins that increase with page count. Thicker books need more gutter space because pages curve more dramatically toward the binding. A 100-page book might work fine with 0.375 inches. A 600-page book needs 0.875 inches or more.

Vellum's default inside margin is 0.875 inches, which handles most books. If you've customized this setting and made it smaller, that's likely your problem. If your book exceeds 700 pages, you might need to increase the inside margin beyond Vellum's default.

To fix it: Open your Vellum project. Go to File, then Print Settings. Find the Inside Margin option and increase it slightly. Vellum recommends adding a small buffer beyond KDP's stated minimum because Amazon's automated checks flag files where even a single pixel crosses the threshold.

Export a new PDF after changing this setting. Upload the new file. The gutter error should clear.

Wide Distribution: IngramSpark Settings

If you distribute through IngramSpark in addition to KDP, you might wonder if you need different files. Good news: both platforms use the same bleed specifications. Vellum's default 0.125-inch bleed region satisfies both KDP and IngramSpark requirements.

The same PDF works for both platforms. Export once from Vellum, upload to both. At IngramSpark, you'll also find a bleed setting during setup. Select the option that matches your file, same as with KDP.

Some authors export separate files for each platform because they want slightly different settings (paper color, binding options). But for bleed purposes, the same interior PDF works everywhere. Vellum built it that way deliberately.

Does Bleed Affect Printing Cost?

No. KDP charges the same printing cost whether you select bleed or no bleed. The pricing calculator considers trim size, page count, and ink type (black and white versus color). Bleed settings don't factor into the equation.

This means you can make design decisions based purely on aesthetics. If you want chapter backgrounds that extend to the page edge, use them. If you prefer clean margins with no decorative elements touching boundaries, that works too. The cost is identical either way.

Checking Your Book After Upload

After your file passes validation, KDP provides a preview tool. Use it. Look specifically at pages where you expect edge-to-edge content. Verify that images extend properly. Check that backgrounds don't have unexpected white edges.

The preview isn't perfect. It's a simulation of what your book might look like. The actual printed copy is the final test. Order a proof copy before making your book available for sale. Hold it. Flip through it. Check the gutter. Check the margins. Check pages with full-bleed images.

Amazon's "Look Inside" preview is a separate system with its own quirks. It regenerates your book using Amazon's software, and the results don't always match your actual print file. Give it a couple weeks to update after you upload a new version. If something looks wrong in Look Inside but correct in your PDF and proof copy, the proof is what matters.

Troubleshooting Persistent Errors

If you've matched your bleed setting to your file and still get errors, check these possibilities:

Outdated Vellum version. Open Vellum, click the menu, and select Check for Updates. Vellum occasionally updates to accommodate changes in KDP's requirements. An older version might generate files that trigger new validation rules.

Corrupted export. Delete your exported PDF and generate a fresh one. File corruption during export is rare but possible. A new export takes seconds and eliminates this variable.

Browser caching. If you've uploaded multiple versions during troubleshooting, your browser might be showing cached error states. Clear your browser cache or try a different browser. Upload the file fresh.

Actual trim size mismatch. Double-check that your Vellum project's trim size matches what you selected at KDP. If you set up the KDP book as 5.5x8.5 but your Vellum project is 6x9, that's a genuine mismatch unrelated to bleed.

The Simple Mental Model

Bleed is extra space for the printer's cutting tolerance. When your design touches the page edge, Vellum adds that extra space. KDP needs to know whether to expect a file with that extra space or without it.

Your only job during upload is to tell KDP the truth about your file. Did Vellum add bleed? Select "Bleed." Did Vellum not add bleed? Select "No Bleed." Match the setting to the file, and the error disappears.

The trim size you select is always the final size of your book after printing and cutting. It never includes the bleed region. A 6x9 book is 6x9 whether it has bleed or not. The bleed setting tells KDP what to expect from your PDF dimensions, not what size book you want to produce.

That's the entire concept. Everything else is implementation details.