Resizing pictures with Irfanview


Staff member
Oct 29, 2003
Abbeville, Louisiana
Bensen B8MG
Lot's of digital cameras these days take multi-megapixel images. They look really good on the screen and are very large with lots of detail, but how do you get 'em on the Forum? The forum software has a 150K file size limit, so we need to learn to shrink those pictures down to size without degrading the quality if possible.

If you don't have a high-end program like Photoshop or Paint Shop Pro, you can download a free copy of Irfanview here. It will allow you to resize your pictures, add a little digital compression to reduce file size, and lots more.

This tutorial will deal with resizing and compression.


First I opened a picture of Rick Martin's GyroBee. I took this picture this year at Bensen Days. I used a 2 MegaPixel camera on hi-resolution which produced a 1600 x 1200 pixel image at 879 Kbyte.

We'll see about cutting that down to size.

Resizing pictures with Irfanview

You can see how large the picture is on the screen, so I clicked the 'Image' tab and selected the 'Resize/Resample' option on the dropdown menu.

Resizing pictures with Irfanview

On the Resize/Resample panel you have many options for resizing. You can select pixels or percentages, specify the image size, etc.
Or you can do what I did. I just selected the 640x 480 size on the right hand side. This will give you an image about 9 inches wide on your computer screen when it's set at 800x600 resolution.

Resizing pictures with Irfanview

Now you can see how it looks at 640 x 480. I'll also attach the final picture at the bottom of this post.
At this point you may want to use some of the other features in Irfanview like sharpen, rotate, add effects, etc. I hit this picture with the Sharpen option under the Image tab before saving it.

Resizing pictures with Irfanview


Once I had resized the picture to 640 x 480, I saved it to my hard drive. But it was still too large at 238 Kbytes, so I went back and saved it again but using the compression slider on the right hand side of the 'Save Picture As' panel.

Resizing pictures with Irfanview

Setting the slider on 100 will save the picture at best quality and no compression, like the first time I saved the above picture. I then set it at 90 and saved it again. This time it saved it at ~100Kb, at the same size, and hardly any artifacting. Artifacting is the little squiggly blobs you get on the edges of the the lines in a picture when you compress it too much. At a value of 80 on the compression slider I started to get some artifacting and the file size was ~70Kb. At a compression value of 70 the artifacting was more noticable and file size was ~55Kb.

I will usually use the least amount of compression I can to get the file size under 150Kb. But sometimes more compression is needed. Pictures will lots of bright colors take up more space that one with muted shades of predominately one color.

Play around with these settings and see what works for you. After a little practice you'll be able to resize, compress, and post 'em like a pro! :)

P.S. Here is the finished photo I used in the tutorial above.


  • Resizing pictures with Irfanview
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Excellent walk through.

walk through

walk through

Yes that is something. If I can't get it know then I must be stupid. I will try it. Thank you for the walk through.
Thanks Mike,
I have been using Irfranview since it was first recommended. I tried both methods, size and compression, but never together. I wish you caould adjust them by Kilobytes on a slider instead of saving and checking saving and checking saving and checking. Lazy me, I guess?
Can you resize multiple pictures at once? I know that you can in Picasa,
Without question the free software you mentioned is quite good, there are many others out there for M$ users which are almost as good and offer more features; i.e, the ability to "crop" a given JPG or GIF image. For example, one can quickly "cut out" and remove the grass patch in front and/or cut or remove the right or left sides of the structure behind what appears to be a rather nice looking gyro.

I wish you caould adjust them by Kilobytes on a slider instead of saving and checking saving and checking saving and checking. Lazy me, I guess?

Tom, that is what sucks. I have tried so many different programs, I must have at least 6 or 7 available. Adobe is junk, all the programs I get with cameras are junk, (I have Canon, Fuji, Kodak, Samsung, one touch, and Micro graphix just to name a few that aren't preloaded on the puter's I have....what the hell else could you possibly find that should be better but is so lame???) The best one I use and keep coming back to is STILL an old (1996) MicroGraphix Picture Publisher LE. Can you believe it??? In 12 years NOBODY has come up with a better handling PPL!!!! Morons....and not from Florida, either.

IF anyone has a better way to do this, please post. What I wind up doing is saving the pic to a file browser which I keep open, and each time I resize I just switch to the open browser to see if I hit the 149 kb size. This usually takes 2 or 3 tries, and what a bloody waste of time that is.
IF anyone has a better way to do this, please post.

If I may suggest, use your Internet Search Engine and search for PAINT SHOP PRO.

There's a version, I think it's v1.3 or so which is a free dl ...

D/L it and play with it for about ten minutes or so and you'll see what I'm talking about; it only works on M$ systems but if you were to switch over to Linux, you'd be amazed at what's out there for FREE in this regard!

Hope this helps :)