Why WordPress Renamed Your Photo to -scaled.jpg (and Shrank It)

Published 13 October 2026 · by Tekiba

What WordPress does to a big upload

WordPress's own developer reference for big_image_size_threshold, read on 13 October 2026, describes it in two sentences:

If the original image width or height is above the threshold, it will be scaled down. The threshold is used as max width and max height.

and gives the default as "The threshold value in pixels. Default 2560." The same page says the scaled-down image "will be used as the largest available size". The announcement on the core team's blog, Introducing handling of big images in WordPress 5.3, adds that "the original image file is stored in the uploads directory".

Neither page names the suffix. That comes from the code that runs on upload, wp_create_image_subsizes(), whose comment reads:

Append "-scaled" to the image file name. It will look like "my_image-scaled.jpg".

Put together, a 2560 pixels limit works like this. A 4032×3024 phone photo is over it, so WordPress makes a 2560×1920 copy called IMG_1234-scaled.jpg, and that is the file your posts point at when they ask for the full size. A photo with both sides within it is left alone.

Rotation, file names and the Media Library

• Rotation. In the same pass, WordPress turns the scaled copy the right way up, following the rotation tag a phone writes. If a photo is under the threshold but carries such a tag, WordPress still writes an upright copy, and this one ends in -rotated instead.
• File names. The smaller sizes your theme uses — thumbnail, medium, large — are made from the original, not from the scaled copy; the code says so ("for best quality"). Their names do not carry -scaled.
• The Media Library. The attachment's file is the scaled copy. The attachment details screen shows an "Original image:" line that links to the file you uploaded.

Three ways to deal with it

1. Choose the size before you upload

If neither side is over the threshold, WordPress has nothing to scale, so there is no -scaled copy, and the image in your posts is the file you made. In SignetDrop:

1. Open SignetDrop and drop the photos for the post.
2. Under Size and format, set Resize to Longest edge and type the size your theme needs. Anything at or below the threshold avoids the scaled copy.
3. Leave Format on JPEG, add a watermark or a naming pattern if you want one, and press Process and download ZIP.

The output also comes out upright, and by default with no EXIF block, so there is no rotation tag left for WordPress to act on and no -rotated copy either. That also means the location and the camera details from a phone photo do not reach your server. Bulk resize and rename photos online goes through the resize and rename settings in more detail.

2. Change the threshold on your site

The filter can raise or lower the threshold, and returning false turns the scaling off. The reference page's "Returning false from the filter callback will disable the scaling" is the whole rule. The one-line form, as the core post gives it:

add_filter( 'big_image_size_threshold', '__return_false' );

It goes in a small plugin or your theme's functions.php. Back the site up before you edit functions.php: a typo there can take the whole site down until it is fixed. Turning scaling off also means every full-size image is whatever was uploaded, however large.

3. Leave it as it is

For most blogs the default is reasonable. A content column is rarely wider than the threshold, the original is kept, and readers get a smaller download.

Things to check before you settle on a size

• High-density screens. A wide content column shown at double density can need close to the threshold. Check your theme's widest image slot and multiply by two before you decide.
• Full-screen backgrounds. A cover image stretched across a large monitor may need more than 2560 pixels. That is the case for raising the threshold rather than resizing down.
• Printing. If people download your photos to print, link to a full-resolution file deliberately rather than relying on the copy WordPress serves.
• One more JPEG save. Each time a JPEG is saved, a little detail is lost. A photo you resize to at or under the threshold is saved once, by you, at the quality you choose. A photo you resize but leave over the threshold is saved twice: once by you, then again by WordPress when it makes the scaled copy.
• Watermarks. A mark drawn on the full-size photo is shrunk along with it when WordPress scales the picture, and thin lettering goes soft. SignetDrop draws the mark after resizing, at the size it will be shown, so put the mark on at the final size rather than before WordPress shrinks it. Watermark multiple photos without uploading them covers the mark itself.

Sizes for marketplaces are a different question, with their own rules: see eBay photo requirements and Etsy listing photos. This page is only about what WordPress does.

Where the free version stops

The free version does ten photos at a time, up to 2048px on the longest edge, with no account, and it does not write our name onto your photos. That ceiling is under WordPress's threshold, so nothing the free version writes is scaled again: with no other setting, a 4032×3024 photo becomes 2048×1536. The paid version is $29 once, not a subscription; you need it to write exactly the threshold or larger, or to do more than ten at a time. The full split is on the pricing panel.

What this page does not do

It describes WordPress's own code and documentation as they read on one day. Themes, plugins and hosts can change the threshold, add their own resizing, or compress images again, and a later WordPress release could change the default. How your site handles an upload is up to WordPress and your theme, not us.

Questions