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Video & Audio Converters

Convert, crop, or extract audio tracks instantly. Operating 100% locally using WebAssembly, your heavy video and audio streams are never uploaded over the internet.

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.

Video & Audio Converter

Extract audio from video or convert audio files between popular formats.

Advanced Media Tools

Extract AudioTrim Video

100% In-Browser Isolation Verified

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

Verify Audit Protocol

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.

Secure Client-Side Media

Your personal video recordings, voice notes, and media files remain safely on your machine. No server-side transcoders ever view, process, or keep copies of your media files.

Save Network Bandwidth

Traditional web converters consume double your internet data (uploading the heavy video file and downloading it back). DuckConvert executes everything inside RAM, wasting 0MB of internet data.

Hardware Accelerated

Modern browsers run WebAssembly instructions at near-native compiling speeds. Experience blazing-fast compression and trimming utilizing your local multi-core processor.

How FFmpeg WebAssembly Powers Offline Media Conversion

Historically, digital media conversion was incredibly taxing, requiring specialized command-line binaries compiled specifically for individual operating systems (Linux, macOS, Windows). Executing these processes inside a sandboxed web browser was deemed impossible.

With the emergence of WebAssembly (WASM), developer toolchains can compile raw C and C++ source repositories directly into platform-independent instruction sets. Under the hood, DuckConvert utilizes the official @ffmpeg/ffmpeg package:

The Client-Side Transcoding Process:

  1. File System Mapping: The chosen media file is read into memory, creating a virtual file node inside FFmpeg's localized in-memory virtual file system (MEMFS).
  2. Multi-threaded Execution: The browser spawns concurrent web worker threads that decode the input container streams, analyze raw audio and video packets, and feed them through requested demuxers.
  3. Target Codec Generation: FFmpeg's encoders compress the raw frames, write them to a new output node inside MEMFS, and dump the finalized byte buffers back into a JavaScript Blob for rapid local download.

Video & Audio Converters FAQs

DuckConvert achieves near-native video processing speeds in your web browser by utilizing WebAssembly (WASM). We compile FFmpeg—the industry-standard, high-performance multimedia framework—into highly optimized WASM binary code. When you run a conversion, your browser executes this code in a separate background thread (Web Worker), which directly manipulates the raw file bytes in memory without touching an external server.
We support a wide array of audio and video formats, including MP4, WebM, MKV, AVI, MOV, FLV, MP3, WAV, OGG, M4A, and animated GIF. You can also transcode and convert between different containers or change codecs (such as H.264, VP9, or AAC) entirely offline.
The very first time you convert a video or audio file, DuckConvert needs to download the compressed WebAssembly binaries (FFmpeg Core) to your local browser storage. This binary payload is roughly 25-30MB. Once downloaded, the browser caches it using CacheStorage. Subsequent visits will load immediately and run instantly, even if you are completely offline.
The primary limitation is your computer's system memory (RAM) and browser storage limits. Because browsers run inside a sandboxed environment, they are typically allocated a portion of your system's RAM (usually up to 2-4GB). For optimal performance, we recommend converting media files under 500MB, although modern desktop machines can comfortably process larger streams.

Explore More Video & Audio Tools

Browse our selection of modern, secure media processing tools running fully inside your browser.

Video Trimmer

Trim or cut video files with high-precision offline.

Open Tool

Audio Extractor

Rip and extract audio tracks from any video file.

Open Tool