Well, there are several ways with which you can resize your photos. I would suggest the following ways for the purpose-
Using online services
There are several web services available which will help you resize your photos. Some of the worthwhile examples can be picresize,Resize Your Image,Shrink Pictures,Web Resizer and Resize Pic. Upload the images to the service. The services have a maximum size permitted. Almost all the services offer you several options to choose from. Select the quality you want. Set the quality of the output image. Download the resized image.
Using MS Paint
Microsoft Paint can be a good option to resize your image files. Launch MS Paint. Navigate to the image you would wish to resize. Click on the Resize option. If you are running the newer version of MS Office, it should be available under Home tab. In the older versions, you can find it under Images tab. Ensure that you have checked Keep Aspect Ratio box. Now, choose the resize method depending upon whether you want to use Pixel Size or Percentage. I would advise using Percentage option. Click on OK. Your image will be resized. Once done, click on Save As and save the file with the file name of your choice.
Open the file you want to resize in Google Picasa. If the image is not in your Picasa library, you may need to add it. Click on File and choose Export Picture to Folder. Choose the folder you want to save it. Now choose the resize option under Resize to radio option. Also click on the Image Size drop down box and choose the quality. I advise to use the Automatic option. Click on Export to save the file.
There are several other tools you can use to resize your images. Photoshop and GIMP are a couple of other services that are really helpful in getting your image files resized.
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