FREE portable utility

Tom's PNG to ICO Converter

A lightweight Windows tool to convert PNG images (including transparency) into clean Windows .ICO icon files. Drag & drop friendly, fast, and made for app icons, shortcuts, and folders.

Windows 10 / 11 Single EXE Drag & drop Transparency supported No install
Quick start Pad vs Crop Troubleshooting

At a glance

  • Drop PNGs or folders — files queue automatically
  • Select output size (16–256). Default is 256×256.
  • Choose Pad (recommended) or Crop for non-square images
  • Saves to an _icons folder next to your PNGs
  • Shows a clear conversion log (success + errors)
Made by Tom Dahne — TomDahne.com

1) What is this?

Tom's PNG to ICO Converter turns one or more PNG files into Windows ICO icon files. It preserves transparency and scales cleanly so your icons don’t get weird dark halos.

ICO basics: an .ico file is the icon format Windows uses for apps, shortcuts, folders, and taskbar/pinned items.

2) Quick start

  1. Run TomsPngToIco.exe.
  2. Drag & drop PNG file(s) (or a folder) onto the drop area.
  3. Pick an Icon size (16, 24, 32, 48, 64, 128, or 256).
  4. Choose Pad or Crop for non-square images (Pad is recommended).
  5. Click Convert.
Tip: For most app icons, start with a high-quality square PNG (e.g. 512×512 or 1024×1024), then export 256×256.

3) Where the ICO files go

For each input PNG, the ICO is created in an _icons subfolder next to the source file: 

C:\Images\logo.png        → C:\Images\_icons\logo.ico
C:\Projects\app-icon.png  → C:\Projects\_icons\app-icon.ico
The _icons folder is created automatically if it doesn’t exist.

4) Pad vs. Crop (non-square PNGs)

If your PNG isn’t square, Windows icons still need a square canvas. This tool gives you two options:

Pad to square (recommended)

  • Keeps the entire image
  • Adds transparent space on the shorter side
  • Best for logos and badges

Crop to square (center crop)

  • Fills the square more aggressively
  • Crops equally from the left/right or top/bottom
  • Best for photos or centered subjects
Heads up: If your logo has text near the edges, crop mode can cut it off. Pad mode is safer for “clean” brand icons.

5) Icon sizes

You choose a single output size using the radio buttons. Default is 256×256.

Size Common use
16×16Small toolbar / legacy UI
24×24UI icons in some apps
32×32Common app icon size
48×48Shortcuts / medium UI
64×64High-res UI, tiles
128×128Large UI / previews
256×256Windows Explorer large icons (recommended)
If you need a “multi-size” ICO (one file containing multiple sizes), that can be added later — this version outputs the size you select.

6) Best results checklist

  • Start with a high-res PNG (512×512 or more is ideal).
  • Use a transparent background where possible (looks clean on any theme).
  • Keep important details away from the edges (Windows sometimes adds padding when displaying).
  • For non-square logos, use Pad mode to avoid accidental cropping.

7) Troubleshooting

Windows SmartScreen warning

  • Right-click the EXE → Properties → check Unblock → OK.
  • This is common for new portable utilities.

“Skipped non-PNG files”

  • The tool only converts .png files.
  • If you dropped a folder, it will scan and queue only PNG files found inside.

Output looks blurry

  • Use a higher-resolution source PNG (e.g. 512×512+).
  • Try a larger output size (128 or 256).
  • If your source image is tiny (e.g. 32×32), scaling up can’t invent detail.

8) Technical details (for nerds)

  • Language: C++17
  • UI: Win32 native (DPI-aware)
  • PNG decode: Windows GDI+ (built in)
  • Scaling: Bilinear interpolation with alpha handling
  • Dependencies: none (single EXE)
Bonus tip: When Windows doesn’t refresh an icon right away, try restarting Explorer (or clear the icon cache). Windows loves to aggressively cache icons like a little gremlin.