Thumbler

High-quality pictures can be taken even with mobile phones nowadays, and became an important resource in computer use. They make up a large array of objects, such as textures, or even profile pictures, but you might need them under strict size specifications. In this regard, Thumbler comes as a batch image resizer.

Convert multiple pictures at a time

Although you’re taken through a setup process to make things work, the application doesn’t make changes to system registry entries, so you can even deploy it on a thumb drive in case you want to use it on other computers as well. Note, however, that you need to have .NET Framework installed, even to go through the steps of the installer.
As far as the visual design is concerned, the application keeps things simple, but in an intuitive manner overall. A couple of fields need to be fitted with the source and destination folders for conversion, while the rest of the space holds all management options to define the output.

Easily set output size and quality

The application is a batch conversion tools, so loading items of interest is a pretty comfortable operation, meaning you need to load an entire directory of pictures. These can be under formats like JPEG, PNG, TIFF, BMP and GIF. Note, however, that there’s no possibility to select a different output format, so the result is the same as input.
In terms of renaming parameters, these are quite easy to handle. You can choose to preserve aspect ratio just so output doesn’t differ a lot from input. You also get the chance to set width and height of the result, as well as the quality, through a dedicated slider.

To end with

Bottom line is that you can encounter various limitations when working with pictures, such as size specifications when uploading a profile picture. As such, Thumbler comes with a set of intuitive tools which help you convert multiple pictures at a time to meet a particular set of size values.