Very low quality when exporting from Final Cut

Hi, newbie here, please, how do I export from Final Cut without losing the quality of the original? It seems every time I export, no matter what I do, the video gets very pixelated and the audio loses all quality, even though my project is in High Definition and the audio is perfect there. Please help!

Make sure you don't have the viewer in proxy mode, else it will export proxy resolution files. Also try exporting straight from FCPX using these settings:

File>Share>Master File>Settings
Format: Computer
Video codec: H.264 Faster Encode
Resolution: 1920 x 1080

That is a good general-purpose codec at a sufficiently high bitrate that it looks pretty good. In general using "Faster Encode" produces nearly as good quality as "H264 Better Quality", but you could also try that if you want.

You can export to ProRes 422, which would be preferred if you were doing further editing on that output file. However that will produce a much bigger file. To export to ProRes, choose Format: Video and Audio, and Video codec: "Source - Apple ProRes 422"

I was having the same issue when exporting to mail. it just comes out low quality.
I don’t use proxy?

Until you're familiar with compression settings start by only using the export presets offered.
If there's a particular FCPX preset creating the issue, if you mention that, perhaps I can recommend custom settings.
Always think about the intended use of your exported video since doing more post work, desktop playback, upload to a web video service, iOS device may all require different settings.