ACX Cover Art Requirements: Audible Audiobook Cover Size and Rules

Your ebook cover is a tall rectangle. Audible wants a square, and that one difference is behind most cover rejections. Here are the official ACX cover art requirements in one sentence: your file must be a true 1:1 square of at least 2400 x 2400 pixels, saved as a high-quality JPG, PNG, or TIF in RGB color mode, and it must clearly display the title and author name without any extra clutter.

The common mistake is assuming the existing ebook or paperback cover will do. It will not, and a rejected cover can cost you another review cycle. The rest of this guide goes through each rule, then shows how to rebuild a rectangular cover as a square and how to check the file before you upload it.

A cover that is a few pixels short of 2400 x 2400 fails the same way as one that is far too small. Check the numbers before you upload.

Understanding the Technical Specs for Audible Cover Art

The rules for audiobook cover size are strict because Audible needs a file that looks professional on everything from a massive high-definition tablet to a tiny smartphone screen. According to the official ACX cover art requirements page, your file must be at least 2400 x 2400 pixels. A file smaller than that simply does not meet the requirement, so there is no point uploading it and hoping. This size ensures that even when the cover is scaled down for a mobile app interface, the text remains sharp and the imagery recognizable.

Beyond the dimensions, you need to pay attention to your color mode. Most print designers work in CMYK, which is optimized for ink on paper. However, digital screens rely on RGB color. If you upload a CMYK file, the colors will often look dull or "off" when displayed on a device. Always export your final file as an RGB JPG, PNG, or TIF, and make sure your resolution is at least 72 dpi to keep the image crisp.

Why You Cannot Just Add Borders to Your Ebook Cover

The single most common mistake I see is taking a rectangular ebook cover and adding white or black bars to the sides to force it into a square. Please do not do this. ACX's own requirements page shows a cover with added borders as an example of what is not acceptable, and it asks for artwork that fills the entire square. It also looks like an afterthought in a store full of covers that were designed as squares.

Instead, you should rebuild your layout. If you have the original design files, move your title and author name into a square composition. This often means rearranging the elements so the text remains readable at a small thumbnail size. If you are starting from scratch or need help ensuring your cover reflects your story, my guide on how to make a book cover can walk you through the essential design principles.

If you are unsure how to design a cover that stands out, you should read my guide on how to make a book cover next.

How to Turn a Rectangular Cover Into a Square One

If you have the layered design file, or a designer who does, this is an hour of work and not a redesign. The order matters, because doing it the other way round is how text ends up cropped.

Start a new square canvas. Make it 3000 x 3000 pixels in RGB. Working a little above the 2400 minimum gives you room to crop or straighten without falling under the limit.
Place the artwork first, without the text. Scale the background image until it fills the square edge to edge. If the art is too narrow, extend the background (sky, texture, flat color) so it reaches the edges. Do not fill the gap with bars.
Re-set the title and author name. A tall cover stacks text vertically with space to spare. A square has less height, so the title usually needs to be larger and on fewer lines. Keep the same fonts and colors so the audiobook is recognizably the same book.
Remove anything that belongs to another format. Barcodes, price stickers, "ebook" or "paperback" labels, and badges from other stores all need to go.
Test it small. Shrink the cover to about the size of a postage stamp on your screen. If you cannot read the title, a listener scrolling on a phone cannot either.
Export and check the file. Save as a JPG in RGB at high quality, then confirm the file is under 8 MB.

How to Check Your File Before You Upload

You do not need design software to confirm the numbers. On a Mac, open the image in Preview and choose Tools, then Show Inspector: it lists the pixel dimensions and the color model, which should read RGB. On Windows, right-click the file, choose Properties, and open the Details tab to see the width and height in pixels. On either system the file size is shown in the file's info or properties window.

Two things catch people at this stage. The first is a cover that is square but too small, for example 1600 x 1600: enlarging it to 2400 in an image editor meets the number but makes the text soft, and blurry text is on the list of things ACX will not accept. Go back to the source file and export it larger. The second is a file that is the right size but saved in CMYK because it came from the print cover. Convert it to RGB and export again.

What Must Be Included and What Must Be Excluded

Your cover is your first impression, but it also has to follow a "do not" list to stay out of trouble. You must clearly show the title and author name. Audible does not require the narrator's name, so you can leave that off if you prefer. What you cannot include is pixelated or blurry text, Audible logos, or references to other marketplaces. If your design has a barcode or a "best seller" badge from another site, remove it before uploading.

Keep in mind that Audible may place an "Only from Audible" graphic on your cover if you are in an exclusive distribution agreement. This means you should keep your main design elements and text away from the extreme corners and edges. If you crowd your text too close to the border, the Audible badge might accidentally cover up your book's title, which is not the impression you want to make. Keep the important things toward the middle.

Technical Summary Table

Requirement	Specification
Dimensions	2400 x 2400 pixels minimum
Shape	Square, filling the entire 1:1 ratio (not rectangular)
Resolution	At least 72 dpi
Color Depth	24-bit (True Color) minimum
File Format	JPG, PNG, or TIF
Color Mode	RGB (not CMYK)
Max File Size	8 MB

A Simple Checklist for Your Submission

Before you hit the submit button, run through this quick checklist to save yourself a potential 10-business-day wait for a rejection. The cover is only half of the submission. Once the art is settled, you still need to ensure your audio files are perfect. You can learn more about the technical side by reviewing audiobook file formats and specs for Audible to ensure your sound quality matches your visuals.

Is the file a true 1:1 square, at least 2400 x 2400 pixels?
Are all fonts crisp and readable at a small size?
Did you remove any barcodes, QR codes, or references to physical CDs?
Is the file under 8 MB in size?
Are all images on the cover fully licensed for your use?

Finally, be aware that ACX maintains specific policies regarding audio production. The official ACX audio submission requirements (last updated April 15, 2026) state that unauthorized use of text-to-speech, AI, or automated recordings in ACX titles is prohibited. If you are using AI tools to create your narration, you should understand the current ACX policy on AI narration and consider whether a wide distribution strategy is a better fit for your project. For the AI narration itself, ElevenLabs is the voice platform Audie points authors to (that is an affiliate link, and Audie may earn a commission if you sign up). Policies do change, so check them again before each release, and always ensure your audio meets the technical standards outlined in the ACX audio submission requirements checklist.

Preparing for a Smooth Upload

A square file that already meets every spec is one less reason for your title to be sent back. If you need help with the actual process of getting your book into the Audible system, you can read my guide on how to upload your audiobook to Audible step by step.

Whatever tools you used to make the cover, the responsibility for meeting these technical specs rests with you as the publisher. Start early, double-check your file against the checklist above, and you will have one less thing to worry about when you finally click publish.

FAQ

Why does my cover art keep getting rejected by the system?

Rejections are usually due to the file not meeting the strict 2400 x 2400 pixel square requirement or the inclusion of forbidden elements like barcodes, watermarks, or blurry text. Make sure your file is not a rectangular image with added borders, as ACX lists that as unacceptable. Double-check that your file size is under 8 MB and that you are using the RGB color profile rather than a print-focused CMYK profile.

Can I use the same cover for my ebook and my audiobook?

You can use the same design assets, but you cannot use the exact same file. Because book covers are typically rectangular and audiobook covers must be square, you will need to open your design software and recompose the layout. Keep the branding and imagery consistent, but ensure the title and author name are clear and centered for the square format to ensure readability at thumbnail sizes.

What happens if I use AI to generate my cover art?

You are welcome to use AI tools to generate your cover artwork, but you must ensure you hold the full rights to the final image. You are still responsible for exporting that image into a 2400 x 2400 pixel square that meets all other ACX rules. Regardless of how the art is made, it must clearly display the title and author name and avoid any prohibited content such as blurry text or third-party copyright claims.

Do I have to include the narrator's name on the cover?

No, the narrator's name is not required on your cover art by ACX. You should prioritize making the title and the author name as legible and prominent as possible. If you have extra space, you can include the narrator, but it is not a mandatory field for your cover to be accepted, and extra text is harder to read at thumbnail size.

Where can I find the official requirements for audio?

The technical requirements for audio are separate from the cover art requirements and can be found on the official ACX audio submission requirements page. You should review these alongside your cover art checklist to ensure your entire project is compliant before you begin your upload process. Both sets of rules apply if you are working out how to create an audiobook for Audible.

Square, 2400 x 2400 or larger, RGB, under 8 MB, with the title and author readable at thumbnail size. Get those right and the cover will not be what holds you up.

And when the cover is sorted and you are ready for the audio itself, come and create your audiobook with Audie. You upload your manuscript, choose your voices, and download chaptered files. The Audie pricing page shows what it costs for a book of your length.