I thought ChatGPT could help so here is what I asked it: “I’ve got 5 jpg files to adjust. They have white borders that are too big. I need to crop them. I have Irfanview for Windows and noticed that I can choose Edit , Auto-crop broders show selection and then use the mouse to adjust. I can see the size at the top (w and h). I can do this for each one so that I end up with all pictures the same size. One minor concern however. My pictures could be slightly off-centered because I am adjsuting manually with the mouse. These will be going into a slider on a website. Thoughts?”

Great question, and you’re right to think about consistency when preparing images for a slider. Here are a few thoughts and options to keep your workflow efficient and your output polished:

What You’re Doing Now
Using IrfanView’s Auto-crop + manual fine-tuning works well for a quick fix. But you’re right — manual mouse adjustments can introduce minor inconsistencies, especially in:

• Centering
• Image alignment
• Final pixel dimensions (even a few px off looks jumpy in a slider)

🔍 What’s the Risk? In a slider, inconsistent image sizes or alignment can cause:

• The content area to shift or “jump”
• Visual jitter or flicker between slides
• Misaligned overlays (text or buttons)

🔧 Options to Improve Consistency

Option 1: IrfanView Batch Crop with Fixed Size. You could:

1. Open one image, auto-crop and manually adjust until perfect.
2. Note the exact crop dimensions and top-left coordinates.
3. Apply the same crop box to all 5 images using:
• Edit > Create Custom Crop Selection (Shift + C)
• Then use Edit > Crop selection
• Or go to File > Batch Conversion > Advanced and enter those crop values under Set crop area.

Option 2: Use a Tool Like GIMP or Photoshop (Optional). If you ever need precision or layering (like logos/text over images), tools like GIMP (free) let you:

• Set fixed aspect ratio or exact pixel dimensions.
• Export all slides to identical canvas sizes.
• Align elements visually and numerically.

Option 3: Use CSS to Mask Inconsistencies (Quick & Dirty).If the images are almost the same size, but you’re short on time:

• Set the slider container size with overflow: hidden
• Use object-fit: cover or a CSS crop trick
• Result: images fill the frame even if slightly off

But this is a hack — better to standardize the source files if possible.

✅ Recommendation: Stick with IrfanView, but:

• Use the custom crop box to lock in consistent dimensions.
• If possible, save the crop preset and apply it to all 5.