Image Converter lets you change image formats, adjust quality, and resize — all inside your browser. It supports PNG, JPEG, WebP, AVIF, GIF, BMP, TIFF, ICO, and ICNS, with no uploads to any server and no file size limits imposed by a backend.
What it does
The tool reads your image files locally, draws them onto an HTML canvas, and re-encodes them in the format you choose. Format-specific options — quality, transparency, bit depth, icon sizes — let you control the output precisely. You can also resize images at the same time, either to exact pixel dimensions or as a percentage of the original.
For SVG output, the tool links to the separate Image to SVG Converter, which uses vector tracing rather than canvas re-encoding.
Who it is for
- Developers who need to prepare images in specific formats for web projects, apps, or APIs.
- Designers converting assets between formats for different platforms or handoff requirements.
- Anyone who needs a favicon or app icon from an existing image without installing software.
- People who want to reduce image file size quickly before uploading to a CMS or sharing online.
When to use each format
- WebP — the best default for web images. Smaller than JPEG and PNG with comparable quality. Use it for photos, hero images, and product shots.
- AVIF — even smaller than WebP at the same quality, but encoding is slower and browser support is slightly narrower. Good for performance-critical pages where you control the environment.
- PNG — lossless with full transparency support. Use it for logos, UI assets, screenshots, and anything where pixel accuracy matters.
- JPEG — widely compatible lossy format. Good for photos when WebP is not an option, or when you need maximum compatibility with older software.
- GIF — limited to 256 colours. Useful for simple graphics or legacy compatibility, but WebP or PNG are better choices for most modern work.
- BMP — uncompressed Windows bitmap. Use only when a specific tool or workflow requires it.
- TIFF — uncompressed, large files. Suited for print workflows and archival use where lossless quality is required.
- ICO — Windows icon format used for favicons and desktop shortcuts. Supports multiple sizes in one file.
- ICNS — macOS icon format for app bundles. Supports sizes from 16px up to 1024px in a single file.
Step-by-step
- Drop images onto the upload area, click to browse, or paste an image from your clipboard.
- Select the target format using the format buttons. The options panel on the left updates to show settings relevant to that format.
- Adjust format options — quality, transparency, bit depth, icon sizes — as needed.
- Choose a resize mode if you want to change dimensions: Original keeps the source size, Dimensions lets you set exact pixel values, and Scale resizes by percentage.
- Click Convert. Results appear below with individual download buttons.
- If you converted multiple images, click Download All as ZIP to get everything in one archive.
Format options explained
- Quality (JPEG, WebP, AVIF) — controls the compression level. 80–90% is a good balance between file size and visual quality for most images.
- Lossless (WebP) — preserves every pixel exactly. File sizes are larger, but there is no quality loss. Useful for UI assets and icons.
- Preserve transparency (PNG) — keeps the alpha channel. Turn it off and set a background colour if you need a flat image without transparency.
- Background colour (JPEG, PNG without transparency) — fills transparent areas before encoding, since JPEG and flat PNG do not support alpha.
- Max colours (GIF) — GIF supports up to 256 colours. Reducing this number makes files smaller but can introduce visible banding.
- Quantization (GIF) — RGB565 gives the best colour accuracy. RGBA4444 preserves transparency at the cost of colour depth.
- Bit depth (BMP) — 32-bit includes an alpha channel; 24-bit does not.
- Multi-size (ICO, ICNS) — embeds multiple icon sizes in a single file. Recommended for favicons and app icons so the OS can pick the best size for each context.
Resize options
- Original — no resizing. The output has the same pixel dimensions as the source.
- Dimensions — set a specific width and height in pixels. Enable the lock icon to maintain the aspect ratio automatically; leave one field empty and the other is calculated for you.
- Scale — resize by a percentage of the original. Use preset buttons (25%, 50%, 75%, 150%, 200%) or type a custom value.
Privacy
All conversion happens in your browser using the Canvas API. Your images are never uploaded to any server. Nothing leaves your device.
Frequently asked questions
How many images can I convert at once?
There is no hard limit. You can add as many files as you like. Keep in mind that very large batches may take longer since each image is processed sequentially in the browser.
Why is AVIF greyed out?
AVIF encoding relies on the browser's native canvas support. Chrome and Edge support it; Firefox and Safari currently do not. If the button is disabled, switch to a Chromium-based browser.
My JPEG output has a white background where the original was transparent. Is that a bug?
No — JPEG does not support transparency. The tool fills transparent areas with the background colour you set in the JPEG options. Change it to match your target background if white is not right.
Can I convert a PNG to ICO for a favicon?
Yes. Select ICO as the target format, enable Multi-size to embed 16, 32, 48, 64, 128, and 256px variants in one file, then convert and download. Most browsers and operating systems will pick the right size automatically.
What is the difference between ICO and ICNS?
ICO is the Windows icon format, used for favicons and desktop shortcuts on Windows. ICNS is the macOS format, required for app bundles distributed on macOS. If you are building a cross-platform desktop app, you will likely need both.
Why is my GIF output showing banding or wrong colours?
GIF is limited to 256 colours. If your source image has many colours or gradients, some colour loss is expected. Try increasing Max colours to 256 and switching quantization to RGB565 for the best result. For images with transparency, use RGBA4444.
Can I convert to SVG?
SVG conversion requires vector tracing, which works differently from format re-encoding. Use the Image to SVG Converter tool, linked in the format selector, for that workflow.
Does resizing affect quality?
Scaling down reduces file size and is generally fine for web use. Scaling up beyond the original dimensions will not add detail — the image will appear softer because the canvas interpolates the missing pixels.