Audiobook cover size: what ACX, Spotify, Apple and others require

An audiobook cover should be a square image, and a 3000 x 3000 pixel RGB JPG meets every major store's size rules as of November 2026. ACX asks for at least 2400 x 2400 pixels, Apple Books requires 3000 x 3000, Spotify recommends 3000 x 3000, Google Play accepts 1,024 to 7,200 pixels a side and Kobo recommends at least 600 x 600. Your ebook cover cannot simply be padded with borders: it has to be redesigned to fill the square.

The cover is the first thing a listener sees in a store, usually as a thumbnail smaller than a postage stamp. The rules below come from each store's own page, read in November 2026.

Below: each store's requirements side by side, the content rules that get covers rejected, and the arithmetic for turning a 1600 x 2560 ebook cover into a square.

What size is an audiobook cover for each store?

An audiobook cover is a square for every major store, required or recommended, with a minimum size between 600 and 3000 pixels depending on where you sell.

Apple Books has the strictest size rule (3000 px) and Kobo the loosest (600 px), with ACX, INaudio, Spotify and Google Play in between, so a cover built to Apple's size works in all six stores:

ACX's page is dated October 2026, INaudio's June 2026, Spotify's asset guide November 2024 and Apple's specification December 2024. RGB is the color mode screens use; CMYK is the mode printers use, and dpi (dots per inch) is a print setting that matters far less than the pixel size. Google Play and Kobo show no date. Google's separate page for its own auto-narrated audiobooks requires a 1:1 cover and recommends 2400 x 2400.

What gets an audiobook cover rejected?

An audiobook cover is rejected for being the wrong shape or for carrying text and images the stores ban.

The stores' pages list these rules, with Apple's from its audiobook formatting guidelines:

• No borders or letterboxing. ACX says a rectangle with borders added is rejected, and INaudio, Spotify's asset guide and Apple Books say the same.
• Title and author must match. ACX wants the title and author visible and matching the credited title. INaudio adds that the cover must match your metadata and opening credits exactly, including the series name and number.
• No store or sales details. ACX bans prices, barcodes, QR codes, running times, websites and competing stores. Apple Books bans prices, competing retailers and the word "Exclusive".
• No physical products. ACX, INaudio and Spotify's asset guide reject images of printed books or CDs, ACX also bans box sets, and Apple Books rejects 3D or mock-up shots and references to a physical format.
• One cover per title. Apple Books does not accept the same cover reused across different titles.

One more ACX detail: for exclusive titles Audible may place an "Only from Audible" badge in the lower-right corner. On ACX's figures that badge reaches 41% of the way in from the lower-right edges, which is about 1230 pixels on a 3000-pixel cover, so keep your title and name out of that corner.

How do you turn an ebook cover into a square audiobook cover?

An ebook cover becomes a square audiobook cover by fitting its height to the square and extending the artwork into the space at the sides.

Here is the arithmetic for a cover at KDP's recommended ebook size of 1600 x 2560 pixels, going to 3000 x 3000:

1. Fit the height. 3000 ÷ 2560 = 1.17, so the ebook cover scales to about 1875 x 3000 pixels.
2. Measure the gap. 3000 − 1875 = 1125 pixels of empty width, about 563 pixels on each side. That is 37.5% of the square.
3. Fill the gap with artwork, not color bars. Extend the background scene, move the title and author into the new width, or rebuild the layout from the original design file.

The other route, fitting the width and cropping, works badly. Scaling 1600 pixels up to 3000 is a factor of 1.875, so the image goes soft and becomes 3000 x 4800. Cropping that to a square keeps only the middle 62.5% of the height, cutting 900 pixels from the top and 900 from the bottom, which usually cuts off the title or your name. Going back to the source artwork is worth the effort.

Which file should you upload?

The file to upload is one 3000 x 3000 pixel JPG in RGB color, and it works for every store in the table.

• 3000 pixels meets Apple Books' minimum and Spotify's recommendation and is above ACX's and Google Play's minimums and Kobo's recommendation.
• RGB is required by ACX and Apple Books, so convert any print-ready CMYK file first.
• JPG is accepted everywhere. A 3000-pixel PNG can be large, and ACX caps files at 8 MB and Kobo at 5 MB, so check the file size before you upload.
• Read the title at thumbnail size. Shrink the finished cover to about 200 pixels wide. If the title is unreadable, enlarge it.

If you are still deciding where to sell, our guide to where you can publish an AI-narrated audiobook covers each store's narration rules, and what ACX is and how it works covers Audible's side.

The bottom line

An audiobook cover is a square, and one 3000 x 3000 pixel RGB JPG with no borders, prices or book mock-ups meets the rules of ACX, INaudio, Spotify, Apple Books, Google Play and Kobo as of November 2026, provided the file stays under 5 MB. Build it by fitting your ebook cover's height to the square and extending the artwork, not by adding bars. AudioForge is a production tool that turns a manuscript into a multi-voice audiobook, and it handles the audio, not the cover, so your next step is the same either way: make the 3000 x 3000 file and check it at thumbnail size before you upload.