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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 Processing

Your files are processed strictly in local device memory. Nothing is uploaded. See how, and check for yourself.

How It Works

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.

Explore More Image & Vector Tools

Discover our selection of client-side graphic utilities running locally in your browser.

Image Compressor

Shrink image file size offline without quality loss.

Open Tool

Image OCR

Extract text from images locally inside your browser.

Open Tool

EXIF Stripper

Remove private metadata/location from photographs.

Open Tool

HEIC Batch Convert

Convert multiple iPhone HEIC photos to JPG at once.

Open Tool

Optimize SVG

Clean up and minify SVG vector paths locally.

Open Tool

From the Blog

Compress PNG Offline - A Private TinyPNG Alternative

Learn how to dramatically reduce the file size of your PNG and JPG images directly in your browser without uploading them to a server.

HEIC to JPG Converter - Free & Private Local Conversion

Learn how to easily convert HEIC photos from your iPhone to standard JPG images directly in your browser. No server uploads, total privacy.

How to Open HEIC Files on Windows

Learn the easiest ways to view HEIC files on a Windows PC without installing sketchy third-party software.

Image to PDF Converter - Secure, Fast, & Local

Convert JPG, PNG, and WebP images to PDF documents directly in your browser. No server uploads, total privacy, and instant results.

Lossless PNG Compression: A Private TinyPNG Alternative

Learn how to reduce PNG file sizes by up to 30% without losing a single pixel of quality, using our completely offline and private image compressor.

Optimize SVG Files Locally - Fast & Free Tool

Minify SVG graphics and remove unnecessary paths using SVGO natively in your browser. Dramatically improve SEO and reduce image load times.

PNG to ICO Converter - Free & Local Icon Generator

Convert PNG images to ICO format for favicons instantly in your browser. 100% private, no server uploads, and completely free.

SVG to PNG Converter - Fast & Free Local Conversion

Easily convert scalable vector graphics (SVG) into standard PNG images locally in your web browser. No uploads, fast processing.

WebP vs AVIF: Which Next-Gen Image Format is Better?

A detailed comparison of WebP and AVIF image formats, their compression capabilities, browser support, and which one you should use for SEO.

What is an AVIF file and why should you use it?

Learn about the AVIF image format, its benefits over JPEG and PNG, and how to start converting your images to AVIF for better web performance.