URL format

<ZONE>

• Your domain name on Cloudflare. Unlike other third-party image resizing services, Image Resizing does not use a separate domain name for an API. Every Cloudflare zone with Image Resizing enabled can handle resizing itself. In URLs used on your website this part can be omitted, so that URLs start with /cdn-cgi/image/.

/cdn-cgi/image/

• A fixed prefix that identifies that this is a special path handled by Cloudflare’s built-in Worker.

<OPTIONS>

• A comma-separated list of options such as width, height, and quality.

<SOURCE-IMAGE>

• An absolute path on the origin server, or an absolute URL (starting with https:// or http://), pointing to an image to resize. The path is not URL-encoded, so the resizing URL can be safely constructed by concatenating /cdn-cgi/image/options and the original image URL. For example: /cdn-cgi/image/width=100/https://s3.example.com/bucket/image.png.

width=x or w=x

• Specifies maximum width of the image in pixels. Exact behavior depends on the fit mode (described below).

height=x or h=x

• Specifies maximum height of the image in pixels. Exact behavior depends on the fit mode (described below).

dpr=x

• Device Pixel Ratio. Default is 1. Multiplier for width/height that makes it easier to specify higher-DPI sizes in <img srcset>.

fit

• Affects interpretation of width and height. All resizing modes preserve aspect ratio. Available modes are:

• fit=scale-down

  • Image will be shrunk in size to fully fit within the given width or height, but will not be enlarged.

• fit=contain

  • Image will be resized (shrunk or enlarged) to be as large as possible within the given width or height while preserving the aspect ratio.

• fit=cover

  • Image will be resized to exactly fill the entire area specified by width and height, and will cropped if necessary.

• fit=crop

  • Image will be shrunk and cropped to fit within the area specified by width and height. The image will not be enlarged. For images smaller than the given dimensions it is the same as scale-down. For images larger than the given dimensions, it is the same as cover.

• fit=pad

  • Image will be resized (shrunk or enlarged) to be as large as possible within the given width or height while preserving the aspect ratio, and the extra area will be filled with a background color (white by default). Transparent background may be very expensive, and it is better to use fit=contain and CSS object-fit: contain property instead.

gravity or g

• Cropping with fit=cover specifies the most important side or point in the image that should not be cropped off.

• gravity=auto

  • The point will be guessed by looking for areas that stand out the most from image background.

• gravity=side and gravity=XxY

  • A side ("left", "right", "top", "bottom") or coordinates specified on a scale from 0.0 (top or left) to 1.0 (bottom or right), 0.5 being the center. The X and Y coordinates are separated by lowercase x. For example, 0x1 means left and bottom, 0.5x0.5 is the center, 0.5x0.33 is a point in the top third of the image.

quality=x or q=x

• Specifies quality for images in JPEG, WebP, and AVIF formats. The quality is in a 1-100 scale, but useful values are between 50 (low quality, small file size) and 90 (high quality, large file size). 85 is the default. When using the PNG format, an explicit quality setting allows use of PNG8 (palette) variant of the format.

format=auto or f=auto

• Allows serving of the WebP or AVIF format to browsers that support it. If this option is not specified, a standard format like JPEG or PNG will be used.

anim=false

• Reduces animations to still images. This setting is recommended to avoid large animated GIF files, or flashing images.

sharpen=x

• Specifies strength of sharpening filter. The value is a floating-point number between 0 (no sharpening) and 10 (maximum). 1 is a recommended value.

blur=x

• Blur radius between 1 (slight blur) and 250 (maximum). Be aware that you cannot use this option to reliably obscure image content, because savvy users can modify an image’s URL and remove the blur option. Use Workers to control which options can be set.

onerror=redirect

• In case of a fatal error that prevents the image from being resized, redirects to the unresized source image URL. This may be useful in case some images require user authentication and cannot be fetched anonymously via Worker. This option should not be used if there is a chance the source image is very large. This option is ignored if the image is from another domain, but you can use it with subdomains.

metadata

• Controls amount of invisible metadata (EXIF data) that should be preserved. Color profiles and EXIF rotation are applied to the image even if the metadata is discarded. Note that if the Polish feature is enabled, all metadata may have been removed already and this option may have no effect.

• metadata=keep

  • Preserve most of the image metadata (including GPS location) when possible.

• metadata=copyright

  • Discard all metadata except EXIF copyright tag. This is the default for JPEG images.

• metadata=none

  • Discard all invisible metadata.