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Image Converters

Favicon ICO Generator — PNG ↔ ICO Online

Instant private convert

Build favicon ICO packs from a PNG (16–256px sizes) or extract the largest frame from an existing ICO—all locally.

Files never leave your browser

Conversion runs on this device. CalculioHub does not receive uploads of your documents, photos, or media. No account required.

Your files
Stay in memory / local processing — not sent to our servers.
Canvas (on-device)
No CDN engine download for conversion — your image bytes stay local.

Recent job names below are stored locally as text only — never the file bytes.

Direction

Files never leave your browser. Batch up to 20 images.

Extracts the largest icon frame as PNG.

Drop ICO images, or browse

ICO → PNG · up to 20 files · max 25.0 MB each · private

Browse files
Size budget0 B / 25.0 MB

Output options

Email = smaller & shareable · Print = high quality · Archive = near-lossless original size

Source dimensions appear after a previewable file loads.
Original · ICO

Drop images to preview

Result · PNG

Converted preview appears here

Plain-English guide

Terms & how it works

Confused by a field? Read the short definitions here while you use the tool.

  • sizes[]

    Favicon sizes

    Square dimensions included in the ICO.

  • frame

    Icon frame

    One resolution entry inside the ICO directory.

  • pack

    ICO container

    Header + directory + image payloads.

When to use this ICO ↔ PNG Converter (Favicon)

Common use cases

  • Convert phone photos for email or web upload limits
  • Switch formats for design handoff without installing apps
  • Batch-friendly one-off conversions in the browser

Localized examples

  • iPhone HEIC photo workflows
  • WebP and PNG web asset preparation

What you get

  • Runs in your browser — nothing uploaded by default
  • Common photo and icon formats supported
  • Free online converter, no watermark

How to Convert ICO ↔ PNG Converter (Favicon) Step-by-Step

  1. 1Choose ICO → PNG or PNG → ICO.
  2. 2Drop your icon or logo.
  3. 3For PNG → ICO, select favicon sizes to include.
  4. 4Preview the result, then download the ICO or PNG.
  5. 5Use Clear before starting a new icon.

Governing formula

ICO = pack(PNG@sizes[]); PNG = extract(maxFrame(ICO))

PNG → ICO scales the logo to each selected size and packs PNG payloads into an ICO. ICO → PNG reads the directory and extracts the largest image.

Use the defaults, then adjust one input at a time to see the result update instantly—no sign up.

Variable definitions

  • sizes[]

    Favicon sizes

    Square dimensions included in the ICO.

  • frame

    Icon frame

    One resolution entry inside the ICO directory.

  • pack

    ICO container

    Header + directory + image payloads.

  • Favicon generation is fully client-side.
  • Prefer a square source logo for best results.

Frequently Asked Questions

16, 32, and 48 cover classic favicons. Add 64–256 for sharper desktop/shortcut icons.

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Community

Reviews & Ratings

See what others think about this tool, then leave your own rating to help improve CalculioHub.

4.8

out of 5.0

4 reviews

Leave a review

Your rating

Aisha K.

Mar 12, 2026

Clean layout and the results update instantly. Exactly what I needed for a quick planning check.

Daniel R.

Feb 28, 2026

Very usable on mobile. Would love a save/export option later, but the math feels solid.

Priya S.

Feb 3, 2026

The FAQ section answered my questions before I even had to search. Smooth dark mode too.

Marcus L.

Jan 19, 2026

Simple inputs, clear outputs. This replaced three bookmarks I used to juggle.

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