Image Converter Tools

Convert your images instantly, privately, and securely. Operating 100% locally in your browser, your photos are never uploaded to any server. Supports WebP, AVIF, HEIC, PNG, JPG, and more.

Universal File Converter: Private & Fast

Convert images, videos, audio, and documents directly in your browser. Your files never leave your device, ensuring 100% privacy and security.

Image Converter

Convert images between modern formats. Ideal for thumbnails, screenshots, and photos.

Looking for more tools?Resize & Crop Images →

100% In-Browser Isolation Verified

Your files are processed strictly in local device memory. Stored zero bytes, audited zero network egress.

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How to convert files with DuckConvert

1

Select Your File

Choose the file you want to convert from your device or drag and drop it into the converter.

2

Choose Output Format

Select your desired output format and any specific settings for your conversion.

3

Convert & Download

Click "Start Conversion" and wait for the local process to finish, then download your new file.

100% Client-Side Privacy

Unlike traditional online converters that store your images on remote servers, DuckConvert processes every pixel inside your browser sandbox. Your personal photos remain secure.

Blazing Fast Local Speed

Bypass the upload and download bottlenecks. Conversions trigger immediately inside RAM, returning your processed files without wasting network bandwidth or internet data.

Runs Fully Offline

Once loaded, DuckConvert can operate completely without an internet connection. Perfect for working securely on trains, flights, or remote locations without secure networks.

Understanding Image Formats: Lossy vs. Lossless Compression

When converting and optimizing images for websites, digital media, or archiving, choosing the right file extension and compression level is vital. Formats are divided into two main categories:

Lossless Compression (PNG, SVG)

Lossless compression preserves every bit of original image data exactly. Retains perfect clarity with no pixelation, making it standard for screenshots, logos, icon graphics, and designs with text. However, file sizes remain large.

Lossy Compression (JPG, WebP, AVIF)

Lossy compression discards imperceptible visual details to massively reduce file sizes. Next-gen formats like WebP and AVIF use advanced prediction filters and chroma subsampling to achieve file sizes up to 80% smaller than PNG while maintaining near-perfect perceived quality.

How Modern Browsers Handle Offline Image Encoding

DuckConvert bypasses backend servers entirely by compiling native compression libraries (like Rust-based OxiPNG or C-based libwebp) into WebAssembly (WASM). This allows your browser to run heavy graphic processing algorithms at near-native speeds. For basic formats, we use the HTML5 Canvas 2D API to render, scale, crop, and output high-quality image blobs dynamically.

Image Converter FAQs

DuckConvert uses modern browser technologies like the HTML5 Canvas API, WebAssembly (WASM), and local JavaScript libraries (such as @jsquash and browser-image-compression) to decode, process, and re-encode image files directly in your computer's RAM. No image data is ever transmitted to an external server, meaning your photos stay 100% private.
We support cross-conversions between JPG, PNG, WebP, AVIF, HEIC, SVG, and GIF. For example, you can convert Apple's HEIC photos from your iPhone into widely compatible JPGs, or convert heavy PNG files into highly optimized next-gen formats like WebP or AVIF.
Since all processing occurs locally on your machine, there is no hard server-imposed file size limit. The only limit is the memory (RAM) and processing power of your device. You can easily process large multi-megapixel camera files or batches of photos offline.
PNG is a lossless format ideal for screenshots, text, or graphics requiring transparent backgrounds, but files are larger. WebP and AVIF are next-generation formats that provide superior lossy and lossless compression. AVIF generally offers the highest compression efficiency (up to 50% smaller than JPG with identical quality), making it the perfect choice for modern web optimization.