How to burn CDs

Different types of disc
There are two main types of CD that you can create with CD burning software - an "audio CD" and a "data CD".


 * An audio CD (officially "Compact Disc Digital Audio", CDDA, or Red Book standard) will play on any standalone CD player, as well as as in your computer and in DVD players.
 * A data CD (sometimes called an MP3 CD where the data it contains are MP3 files) will not normally play on standalone CD players. It will play on computers, most DVD players and in MP3 CD players.

So if you want to play your CD on a standalone player, or give it to others and be sure they'll be able to play it, you'll need to burn an audio CD.

When buying blank CDs for recording/burning, it is strongly recommended that you purchase CD-Rs and not the rewritable CD-RWs.

Audio CDs
Audio CDs always contain high quality uncompressed PCM stereo data at 44100 Hz sample rate, 16-bit resolution. So to burn an audio CD, you should always export the file you want to burn as a 44100 Hz 16-bit stereo WAV or AIFF file. To configure Audacity to do this, please see Burning music files to a CD in the current Manual.
 * For legacy 1.2 and 1.3 versions of Audacity, please see this older Frequently Asked Question on the main Audacity site "How do I save my recording on an audio CD?".

Overburning
Because audio CDs must always contain uncompressed 44100 Hz 16-bit stereo audio, they are necessarily limited on a 650 MB ("Red Book Standard") or 700 MB audio CD to 74 - 80 minutes playing time respectively.

If you need more playing time (for example, to try and accommodate a C90 cassette or two LPs onto one CD), then if both the CD burner and the CD burning software support it, you can "overburn" into the blank CD space so as to extend the playing time by a further few minutes. This gives you the possibility of up to 80 minutes' playing time on a 650 MB disc or up to 86 minutes on a 700 MB disc. Overburning is always done using Disc at Once (DAO) mode in which the tracks are burnt continuously without turning the laser off.

It is also theoretically possible to overburn using "90 minute" (790 MB) or "99 minute" (870 MB) CD-R discs. However there is no guarantee whatsoever that your CD burner will accept such CD-R discs, or that your CD player will play anything other than a Red Book Standard 650 MB disc burned with 74 minutes of audio.

On Windows, Deep Burner (free version available) is reported to be amongst the best programs for successful overburning.



Data CDs/data DVDs
For burning really long files to optical media, you must burn either a "data CD" or a "data DVD". For example, burning MP3 files to a 700 MB "data CD" (sometimes called an "MP3 CD"), and using Audacity's default 128 kbps MP3 export bit rate gives over 11.5 hours' playing time.

If you were to choose a 64 kbps MP3 bit rate, about 23 hours of music would fit on the CD. To change the MP3 export bit rate, select "MP3 Files" in the File Export Dialog then click the button (in 1.3.2 or earlier versions of Audacity, open the  then choose "MP3 Export Setup").

Note that the penalty of reducing the bit rate is lower sound quality (especially so for music, less so for speech).

A single layer 4.7 GB data DVD can accommodate nearly 80 hours of 128 kbps MP3 audio, though some older DVD players won't play DVD data discs, or only those containing certain audio or video formats.

Burning software
Most computers already come with media player software that can burn CDs. For example you can use Windows Media Player (built into Windows computers) or iTunes (built into Mac computers but also available for Windows). In either Windows Media Player or iTunes, drag the files you want to burn from the location you exported them to into a "playlist".

Real Player requires files to be added to "My Library" with its command before burning. If you have not yet created a Real Player library, see and for help burning to CD on Real Player go here.

You can also use a standalone Windows burning program like CDBurnerXP, Deep Burner or Nero (or Burn or Toast  for Mac OS X) to burn your exported files. Most Linux distributions include Brasero or K3B for CD burning. When using standalone burning programs, open the files from within that software, do not drag and drop them from your file manager.

Splitting long recordings into multiple audio files for the CD
Instructions for current Audacity on how to split a long recording into multiple tracks then export as multiple audio files for the CD burn can be found at this page in the Manual.
 * For legacy 1.2 and 1.3 versions of Audacity, please see this older Frequently Asked Question on the main Audacity site "How can I split a long recording into multiple files or CD tracks?".

Gapless burning of continuous material
By default, most CD burners add an appropriate two-second gap between CD tracks. However sometimes you may have a continuous mix or live concert where you want to play the CD without gaps but still want the ability to skip from one CD track to the next using the player controls.

To achieve this you can try turning off the setting in the burning software to add a gap, and/or set the burning software to Disc-At-Once (DAO) mode (if the CD burner and burning software support this). Be sure to use lossless WAV or AIFF files because most lossy formats like MP3 add silence padding. However even this may still result in a very short audible gap between tracks on some CD players.

The more reliable solution is to export a single file for the entire recording, then burn the CD with DAO using a cue sheet. The cue sheet can be generated from exported Audacity labels and specifies the start times of each CD track. This should provide smooth playback across tracks on any CD player that has reasonable support for gapless playback. For instructions, see Cue sheets.