How to convert MP3 to AAC
- Click Choose files or drop your MP3 files into the box above.
- Pick the bitrate (192 kbps by default) and, optionally, trim the start or end.
- Click Convert and download the AAC when it is ready.
MP3 vs AAC
| MP3 | AAC | |
|---|---|---|
| Compression | Lossy | Lossy |
| Typical bitrate | 128–320 kbps | 96–256 kbps |
| Size | 1–2.4 MB per minute | 0.7–2 MB per minute |
| Plays on | Everything: every phone, car stereo, speaker and app | Phones, computers and most modern players |
| Best for | Music and podcasts that must play anywhere | Efficient lossy audio, the successor to MP3 |
About MP3 and AAC
What is MP3?
MP3 is the most compatible audio format there is. It shrinks music to about a tenth of CD size by removing sounds people hardly hear. At 192–320 kbps most listeners cannot tell it from the original, and every device ever made with a speaker can play it.
- Plays on every device
- Small files
- Lossy
- Slightly less efficient than AAC or Opus
What is AAC?
AAC is the codec YouTube, Apple Music and most streaming services use. It was designed as MP3’s successor and gives better sound at the same bitrate. A raw .aac file contains only the audio stream; inside an MP4 container the same audio is usually called M4A.
- Better than MP3 at the same bitrate
- Used by YouTube and Apple
- Raw .aac files lack proper tags and seek poorly
Why GlideConvert?
- Private by design. Your files are converted on your own device by your browser — they are never uploaded to a server. That keeps them private, avoids upload waits and means there is no queue.
- Fast. Images convert in a fraction of a second; video uses your device’s hardware encoder.
- Free. No sign-up, no watermark. 10 images, 5 audio files or one video at a time — Pro lifts the limits and removes ads.
Frequently asked questions
Will converting MP3 to AAC reduce quality?
AAC is a lossy format. At 192 kbps (the default) the result is practically indistinguishable from the original for most listeners; pick 256–320 kbps for the best quality, or 96–128 kbps for speech and podcasts.
Which bitrate should I choose?
128 kbps is fine for speech and podcasts, 192 kbps is great for music, and 256–320 kbps is as good as it gets. Higher bitrates mean bigger files: roughly 1 MB per minute at 128 kbps.
Are song titles, artists and cover art kept?
Yes, where AAC supports them: title, artist, album, track number and similar tags are copied from the MP3 file.
Is there a file size limit?
On the free plan each video or audio file can be up to 500 MB and each image up to 100 MB. With Pro the limit is 4 GB per file. Because everything happens on your device, the practical limit for very large files is your device’s memory.
Are my files uploaded to a server?
No. GlideConvert runs entirely in your browser: images are processed with the browser’s built-in codecs and WebAssembly, video and audio with hardware-accelerated WebCodecs (or a WebAssembly build of FFmpeg for older formats). Nothing is sent anywhere — you can even disconnect from the internet once the page has loaded.
Does it work on iPhone, Android, Mac and Windows?
Yes. It works in any up-to-date browser — Chrome, Edge, Safari, Firefox or Samsung Internet — on phones, tablets and computers, with nothing to install. On phones, extremely large images may be scaled down to fit within the browser’s memory limit; you will see a note if that happens.