Any file up to 500 MB. Drop several files and they come back as one ZIP. Many image, audio and video conversions run in your browser; anything else is uploaded and removed within the hour.
Convert your AAC audio files to the highly efficient OPUS format with our online tool. This conversion is ideal for users looking to standardize their audio library for modern web streaming and real-time communication platforms.
AAC is a widely used lossy compression format optimized for general-purpose audio, while OPUS is a versatile codec designed specifically for low-latency interactive audio and high-quality streaming. When you convert from AAC to OPUS, you are moving from a proprietary standard (MPEG-4) to an open-source, royalty-free container that excels in dynamic bitrates and variable network conditions.
Because both AAC and OPUS are lossy formats, re-encoding will lead to generation loss. Expect a minor degradation in audio fidelity, although the output file size will remain largely similar to the original.
We built this project so anyone can convert files without paywalls, accounts, or hidden limits. Here is what that promise means in practice.
Every converter on ConvertX is free to use: no trials, no premium tiers, and no credit packs. We will never put core conversion features behind a subscription. Whether you convert one photo or a hundred files a week, the price stays zero.
Many image, audio, and video conversions run entirely in your browser. Your files never leave your device for those jobs. When server processing is required for documents or specialized formats, uploads are handled securely and removed automatically — typically within one hour.
A quick guide to strengths and trade-offs of popular formats — so you pick the right one before converting.
Music, podcasts, voice recordings, and sound effects.
Common extensions: MP3, WAV, FLAC, OGG, AAC, M4A, OPUS
Raster and vector graphics for web, print, and photography.
Common extensions: PNG, JPG, WebP, AVIF, GIF, SVG, HEIC, TIFF
Office files, PDFs, ebooks, and plain text.
Common extensions: PDF, DOCX, XLSX, PPTX, ODT, EPUB, TXT
Clips, streams, screen recordings, and movies.
Common extensions: MP4, WebM, MOV, MKV, AVI, MPEG
