How they really differ
Start with what your viewers will look at. If it is your slides or screen, a voice tool like Murf is usually enough and keeps the focus on the content. If you want a presenter to build a personal connection without filming, that is HeyGen's job.
Avatar videos tend to cost more per finished minute than voiceover alone, because you are generating video rather than audio. Compare your monthly output against each plan's limits before choosing.
Commercial-use rights and voice cloning rules depend on the plan for both. Read the terms before you publish on a monetized channel.
Using both
Use a HeyGen presenter for the intro and closing call to action, and Murf narration over the screen-recording or slide sections in between.
The verdict
HeyGen for presenter-led video, Murf for narration over visuals you already have. Test both with the same 60-second script before paying.
Want the full write-up on each? Read our HeyGen review and Murf AI review.