Getting Started with ZIP PNG

Using ZIP PNG will reduce the image payload significantly and increase the website’s performance.

The easiest way to understand ZIP PNG is to see it as an intelligent Content Delivery Network (CDN). The built-in intelligence automatically (or explicitly) optimizes images for the requesting device or browser. In most cases the data traffic generated by images will be reduced up to 90 percent compared to the original images.

Basic Images Transformations

Go to our server URL then append /upload/; after that you can pass these options below, followed by an underscore and a value q_75. Options are separated by coma (configurable to other separator).

After the options put the source of your image, it can be relative to your server or absolute: /

So to get a pretty dog a with 75% compression, you would write:


WordPress Integrations

Enabling ZIP PNG for your WordPress image content is very simple. You can use plugin such as CDN Enabler (free).

CDN URL : Insert our endpoint URL and your URL, for example

Included Directories: wp-content

Exclusions: .php,.js,.css,.eot,.woff,.woff2,.ttf,.svg

Relative Path: check

CDN HTTPS: check

Image Manipulation Options

w : width

int Default: null Description: Sets the target width of the image. If not set, width will be calculated in order to keep aspect ratio.


w_300 :

h : height

int Default: null Description: Sets the target height of the image. If not set, height will be calculated in order to keep aspect ratio.


h_250 :

Using width AND height

example:h_300,w_300 By default setting width and height together, works like defining a rectangle that will define a max-width and max-height and the image will scale propotionally to fit that area without cropping.

By default; width, height, or both will not scale up an image that is smaller than the defined dimensions.

h_300,w_300 :,w_300/

c : crop

bool Default: false Description: When both width and height are set, this allows the image to be cropped so it fills the width x height area.


c_1,h_300,w_300 :,h_300,w_300/

g : gravity

string Default: Center Description: When crop is applied, changing the gravity will define which part of the image is kept inside the crop area. The basic options are: NorthWestNorthNorthEastWestCenterEastSouthWestSouthSouthEast.


g_West :,g_West,h_300,w_300/

r : rotate

string Default: null Description: Apply image rotation (using shear operations) to the image.

example: r_90r_-180,…

r_45 :,h_300,w_300/

o : output

string Default: auto Description: Output format requested, for example you can force the output as jpeg file in case of source file is png. The default auto will try to output the best format for the requesting browser, falling back to the same format as the source image or finally with a fallback to jpg.

If input is passed, no “optimal” format will be attempted. ZipPNG will try to respond with the source format or fallback to jpg.


o_auto :

q : quality

int (0-100) Default: 90 Description: Sets the compression level for the output image. Your best results will be between 70 and 95.


q_75 :

q_20 :

webpl : webp-lossless

int Default: 0 Description: If output is set to webp, it will default to lossy compression, but if you want lossless webp encoding you have to set it to 1.


webpl_1 :,webpl_1/

rf : refresh

Default: false Description: When this parameter is 1, it will force a re-request of the original image and run it throught the transformations and compression again. It will delete the local cached copy.


The nginx server will send headers to prevent caching of this request.

It will also send headers with the command done on the image + info returned by the command identity from Imagemagik.

rf_1 :,rf_1/

bg : background

color (multiple formats) Default: null Description: Sets the background of the canvas for the cases where padding is added to the images. It supports hex, css color names, rgb. Only css color names are supported without quotation marks. For the hex code, the hash # character should be replaced by %23


bg_yellow :,bg_yellow,r_45/

st : strip

int Default: 1 Description: removes exif data and additional color profile. Leaving your image with the default sRGB color profile.


rz : resize

int Default: null Description: The alternative resizing method to -thumbnail.


rz_1 :

moz : mozjpeg

Default: 1 Description: Use moz-jpeg compression library, if 0 it fallsback to the default ImageMagick compression algorithm.

unsh : unsharp

{radius}x{sigma}[+gain][+threshold] Default: null Description: Sharpens an image (despite the unfortunate naming). It basically sharpens via subtracting a blurred, low contrast, version of the image to the image itself. For more details check Imagemagick docs.

example 1:unsh_0x6
example 2:unsh_0.25x0.25+8+0.065

unsh_0x6 :

sh : sharpen

{radius}x{sigma} Default: null Description: Use a Gaussian operator of the given radius and standard deviation (sigma). For more details check Imagemagick docs.

example 1:sh_6
example 2:sh_0x6

sh_0x6 :

blr : blur

{radius}x{sigma} Default: null Description: Apply Blur on a image. For more details check Imagemagick docs.

example 1:blr_2
example 2:blr_1x2

blr_2 :

f : filter

string Default: Lanczos Description: Resizing algorithm, Triangle is a smoother lighter option


sc : scale

Default: null Description: The “-scale” resize operator is a simplified, faster form of the resize command. Useful for fast exact scaling of pixels.