Image Batch Converter

JPG - Advanced options for image conversion

If you only want to convert the image format, there is no need to modify the conversion options, just keep the default.

• Custom

  The image quality of jpg can be adjusted. The higher the value, the higher the quality. The default value is 100.

  After wasm is turned on, the mozjpeg algorithm is used to compress jpg images, which provides a stronger compression effect, but the conversion speed will be slower. For example, the following image CentralPark.jpg Quality 100 The conversion time is 0.07 s (1.1MB) when wasm is turned off, and 0.82 s (862.7KB) when wasm is turned on.

  
  

  Test image information: CentralPark.jpg 2048x490px / 823.9KB

  Image Source : Central_Park_Summer.JPG

  Quality 100	Quality 90	Quality 80	Quality 60	Quality 40	Quality 20	Quality 1
  Quality 100 wasm	Quality 90 wasm	Quality 80 wasm	Quality 60 wasm	Quality 40 wasm	Quality 20 wasm	Quality 1 wasm




• Optimal

  Automatically set wasm to start, and set the quality parameter to 90 to convert jpg, so that the output jpg image quality and image file size achieve the best balance.




• Lossless

  Automatically set the quality parameter to 100 to convert jpg so that the output jpg image does not lose any image details.

  
  

  Theoretically, each time you save a JPG, the image quality will be partially lost. However, in actual conversion tests, it was found that after 10 conversions with a quality of 100, there was no obvious loss in the image quality of the JPG image. For ease of understanding, I named it 'lossless'.

PNG - Advanced options for image conversion

If you only want to convert the image format, there is no need to modify the conversion options, just keep the default.

• Lossless

  The most common PNG format provides the highest image quality and preserves all the details of the image.




• Compression

  Lossy compression of png images

  1. 256 C

     Compress PNG by limiting the number of colors in PNG and controlling the number of colors in PNG within 256.

  2. 256 6000

     Compress PNG by limiting the number of colors in PNG and controlling the number of colors in PNG within 6000.

  3. Tinypng ^Recommend

     Provides a compression algorithm similar to Tinypng, which has a very good compression effect, providing natural color gradients and supporting transparent/translucent features of the alpha channel. After compression, the image quality will be slightly reduced (almost unrecognizable to the naked eye), and the file size of the image will be greatly reduced, which can reduce the size of the png file by about 50-80%.

     
     

     The following is the Tinypng test data (using Apple mac m1):

     
     

     Before : 1918x1731px /4.2MB -> After : 1918x1731px / 1.4MB (-68%) Time : 1.85 s

     
     
     

     Before: 2048x2048px px /984,4KB -> After : 2048x2048px / 731.1KB (-26%) Time : 2.83 s Image Source: https://commons.wikimedia.org/wiki/File:Color_circle_(RGB).png

     

• Fixed Color png

  The number of colors of the custom PNG image ranges from 1 to 30000.

Choose the right png compression method

Usually, using Tinypng compression can achieve a relatively ideal compression effect. However, the following png compression test table shows that in some cases, such as illustrations with multiple gradient colors and png images with solid color blocks, Tinypng will have a more obvious grainy feeling. In this case, you can use 6000c to compress png to retain the smooth gradient effect.

In short, for common PNG material images, please use Tingpng, and for colorful illustration PNG, use 6000c or set the number of colors in the fixed color to achieve the best compression effect.

Comparison data of png compression methods of various to.ImagesTool.com :

Compression method	Tree png
Original image 1918x1731px 4.2MB
Tinypng 1.4MB (-68%) Time : 1.86 s
256 C 1.4MB (-68%) Time : 1.31 s
6000 C 3.8MB (-11%) Time : 3.83 s
Fixed Color 10 414.4KB (-91%) Time : 0.88 s

Compression method	Gradient colour png Image Source: File:Color_circle_(RGB).png
Original image 2048x2048px 984.4KB
Tinypng 731.1KB (-26%) Time : 2.83 s
256 C 93.8KB (-91%) Time : 1.25 s
6000 C 447.9KB (-55%) Time : 2.0 s
Fixed Color 10 30.0KB (-97%) Time : 0.8 s

Compression method	data2 hero earth spirit png Image Source: earth_spirit.png
Original image 1440x1440px 1.5MB
Tinypng 374.3KB (-75%) Time : 1.43 s
256 C 234.3KB (-85%) Time : 0.76 s
6000 C 878.6KB (-42%) Time : 1.69 s
Fiexd Color 10 70.9KB (-96%) Time : 0.47 s

Compression method	earth spirit png Image Source: Earth (blank).png
Original image 2953×2953 px 2.9 MB
Tinypng 977.9KB (-67%) Time : 2.25 s
256 C 861.1KB (-71%) Time : 1.50 s
6000 C 2.9MB (-7%) Time : 3.29 s
Fiexd Color 10 248.6KB (-92%) Time : 1.13 s

WEBP - Advanced options for image conversion

If you only want to convert the image format, there is no need to modify the conversion options, just keep the default.

This is webp refers to a still frame/non-animated webp, if you need to convert webp animation, please use
Convert WEBP animation

• Custom

  The image quality of webp can be adjusted. The higher the value, the higher the quality. The default value is 100.

  
  

  After turning on wasm, use the webp algorithm to compress webp images, which provides similar compression effects, but the conversion speed will be much slower.

  For example, the following image CentralPark.jpg, with a quality of 100, takes 0.15 s (1.4MB) to convert with wasm turned off, and 1.04 s (1.3MB) to convert with wasm turned on. It can be said that there is not much difference between the two, which is different from the wasm situation of jpg, which generally does not need to be turned on.

  
  

  Test image information:CentralPark.jpg 2048x490px / 823.9KB

  Image Source : Central_Park_Summer.JPG

  Quality 100	Quality 90	Quality 80	Quality 60	Quality 40	Quality 20	Quality 1
  Quality 100 wasm	Quality 90 wasm	Quality 80 wasm	Quality 60 wasm	Quality 40 wasm	Quality 20 wasm	Quality 1 wasm




• Optimal

  Automatically set wasm to start, and set the quality parameter to 90 to convert webp, so that the output webp image quality and image file size achieve the best balance.




• Lossless

  Automatically set the quality parameter to 100 to convert webp so that the output webp image does not lose any image details.

  
  

  It is highly recommended to use lossless webp to compress pixel-style images, the compression effect is very good.
  From the following test table, we can see that converting png and gif format pixel art images into lossless webp can reduce the image file size by about 30-60%.

  	Example A	Example B
  gif to webp
  png to webp

  
  

PDF - Advanced options for image conversion

Convert other image types into PDF documents, support modifying PDF image quality and size, and support setting passwords.

• PDF Quality

  The principle of the pdf converter of to.ImagesTool.com is to convert other formats into jpg and then make it into pdf. You can set the image quality of the pdf from 1 to 100. The higher the value, the higher the image quality. After turning on wasm, the mozjpeg algorithm is used.




• model

  Supports many-to-one or one-to-one mode.

  
  

  Merge all files into 1 PDF

  Sort all the images in the file list to generate a PDF file. After selecting this mode, you can drag the files to change the file order.

  Before 5 Image, 15.7 MB Image Source : 01.png02.jpg03.jpg04.jpg05.jpg	After 1 PDF, 41.2KB , 72 Quality wasm , auto size open image-to-pdf.PDF

  
  

  Convert each file into PDF

  Convert each file in the file list to a pdf file.




• PDF Page size

  Original image

  Set the pdf size according to the image size before conversion

  Custom

  Set the width and height of the PDF. The default unit is millimeter (mm). Other units are supported: inch (inch), centimeter (cm), pixel (px), point (pt), pc, em, ex

AVIF - Advanced options for image conversion

If you only want to convert the image format, there is no need to modify the conversion options, just keep the default.

• Custom

  
  

  Quality

  The image quality of avif can be adjusted. The higher the value, the higher the quality. The default value is 86.

  Test image information：CentralPark.jpg 2048x490px / 823.9KB

  Compression strength: 4。

  Image Source : Central_Park_Summer.JPG

  Quality100 Strength 4	Quality90 Strength 4	Quality80 Strength 4	Quality60 Strength 4	Quality40 Strength 4	Quality20 Strength 4	Quality1 Strength 4

  
  

  Compression strength

  You can adjust the compression quality, ranging from 1 to 8. The higher the value, the better the compression effect, but also the longer it takes. The default value is 4.

  We recommend using 4 to strike a balance between compression efficiency and time consumption.

  
  

  From the lowest 1 to the highest 8, there are obvious differences in processing speed, you can learn more about it through the avif compression strength test table below.

  Quality86, Strength : 1-8

  Image Source : Central_Park_Summer.JPG

  Strength 1 0.9 s	Strength 2 1.5 s	Strength 3 2 s	Strength 4 1.47 s	Strength 5 1.48 s	Strength 6 6.70 s	Strength 7 8.37 s	Strength 8 20 s




• Optimal

  Automatically set the image quality to 90 and the compression strength to 4 to convert avif, so that the output avif image quality and image file size achieve the best balance.




• Lossless

  Automatically set the image quality to 100 and the compression strength to 4 to convert avif, so that the output avif picture retains all image details.

  
  

SVG - Advanced options for image conversion

Convert bitmap images to SVG vector images, providing multiple options to choose from

• Illustration

  Illustrations and pixel art

  Original image png 2.0MB	Default svg 3.1MB	Photo - Color Blocks svg 1.0MB	Photo - Pixel svg 656KB	Photo - Reality svg 6.0MB	Illustration-01 svg 2.3MB
  Illustration-02 svg 2.1MB	Poster svg 630KB	Pixel-01 svg 2.2MB	Pixel-02 svg 11.9MB	Pixel-03 svg 4.1MB	Draft svg 193KB





• General

  More parameters can be adjusted

  
  
  




• Pixed

  Pixel Block Sampling

  
  

  Original image	Number of samples 100	Number of samples 500	Number of samples 1000	Number of samples 2000	Number of samples 5000