IrfanView is a simple image viewer software with support for many image formats.

Windows operating system can show images using its image viewer software. This viewer can be enough for some users, but for others, a program with more options and possibilities is necessary.

IrfanView displays images and pictures quickly. The program is compatible with many image formats: PNG, JPG, GIF, animated GIF, BMP, TIFF, etc. In addition, it can play video and sound files, although this is not their primary function.

The program is notable for its simplicity of use and eases of showing the images in a directory. Once installed, we can associate image files with this program, so when we double-click on any image, it will be opened in this program. For example, if we want to see the images in a directory, we can use Windows Explorer and double-click on any image, then it will launch this program and display the selected image. We can now use the left and right arrow keys to scroll through the images. If an image is rotated and we want to change the rotation, we need to press R or L key. R = rotate 45 degrees the image to the right, L = rotate 45 degrees the image to the left.

We can view images in slideshow mode. That is to say; we will select multiple images, which will be displayed one after the other after a few seconds of pause between them. We can choose the images that will be part of the presentation or include all the images from a directory without having to manually select one at a time. We can choose pause time between image and image, display in full screen or window, etc.

Another interesting option is batch conversion and renaming. We can select multiple images and convert them to another format, for example, JPEG to PNG. We can also select multiple images and rename them in batches.

This program has a navigation mode that displays images and thumbnails in directories. This way, we can copy, move, and delete images and copy them to an FTP server or send them by e-mail.

If we are looking for an image and don't find one, we can use this program because it incorporates an internal search engine with which we can search for images in all PC units. In addition to searching by name and extension, we can search in the EXIF and IPTC image fields.

Another interesting option is the possibility of using the program to scan documents or images since it can recognize the connected scanner to our PC, save an image of the scanned document, or even send the scanned document to the printer directly.

IrfanView includes a simple image editor with which we can add text, lines, and shapes, delete parts of the image, freehand, etc. We can crop the image to a specific area or insert another image as a watermark. We can also resize the image with the least loss of quality using one of the following algorithms: Lanczos, B-Spline, Mitchell, Bell, Triangle, and Hermite. It is also possible to add image filters such as: black-and-white, inverted color, color correction, replacement of color, red-eye reduction, sepia, and more.

The program supports plug-ins that extend the basic functionality. For example, we can add the option of Optical Character Recognition (OCR), include a media player, modify EXIF data in JPEG files, and more.

The program can detect whether an image has the wrong extension and will alert us when we open it, offering the possibility of correcting the file extension. For example, if we open a .png file, which in reality is a .jpg file, the program will detect it and can fix the file's extension.

IrfanView can be considered one of the most important image viewers for Windows because during all the years it has been developed, it has been incorporating new functionality and features that no other software image viewer possessed. The first version was launched in the year 1996. The program is free for non-commercial use.