To export a project for YouTube, we have to follow some specific guidelines provided by the support area of the site itself. If you want to check the best possible settings for uploading video, you can visit https://support.google.com/youtube/answer/1722171?hl=en. 

After visiting the page and looking for the specifications, you will see some critical aspects to render a video project such as:

• File container: MP4
• Video codec: H264
• Audio codec: AAC
• Bitrate: Will depend on resolution and frame rate

There are other settings for video, but those are the most critical aspects of a video that you will find in the Blender user interface.

Where are these options? You will find the render output options in the Properties window in a tab called Render output (Figure 9.3):

Before we proceed, it is important to point out a critical setting. We will use Cycles options for all rendered output. Remember to set Cycles as the default engine in the Render options.

Once you open the options, you will see at the top the dimension options where you can pick the resolution and frame rate. By default, Blender will start with a resolution of 1920 x 1080 pixels, which is also known as 1080p. Below the resolution, you can apply a scale factor to that resolution.

For instance, if you want to make a quick test render, set the scale to 25% and the output size will shrink down to only a quarter of the size.

There you will also find the frame rate settings, which is 24 by default.

What if you want to use something else, such as a 4K video? At the top of your panel, you can use presets for lots of video standards (Figure 9.4):

If you pick the preset for 4K UHDTV 2160p video, you will get a resolution of 3840 x 2160 pixels. For other video formats that are not present in the list, you can always use the New Preset option in that same list. Type the name of your preset and press the plus icon.

Blender will use the current resolution you have for the new preset.