Start with where the video is being edited
If your project is already in CapCut, try its speech tool before adding another step. CapCut documents text-to-speech in both its desktop editor and web workflow, with generated narration that can be used in a video project. That keeps picture and narration together.
TTS Lines is an audio preparation tool. It does not edit your footage. Its useful unit is a script line: edit the words, choose a speaker, adjust speed, generate that line, and keep the other clips. Choose it when you need an audio handoff or expect to revise the script in small pieces.
What happens when one sentence changes?
Suppose a three-shot product video has one sentence per shot. The middle sentence names a feature that has changed. In TTS Lines, rewrite that line and regenerate it. Download its MP3, then replace the corresponding narration on your video timeline. You do not need a new recording of the opening and closing lines.
A shorter replacement leaves extra space; a longer one may run into the next shot. Decide whether to shorten the wording, change the delivery speed, or adjust the picture. Keeping a clip separate makes the revision easier to handle, but it does not make different recordings the same length.
Name the files by scene in your editing folder and keep the previous take until you have heard the replacement in context. The ZIP export provides separate clips in line order. Reordering or adding lines can change that order, so do not treat the exported filename as a permanent scene identifier.
Compare the files you actually need
CapCut's published speech page lists direct audio downloads, including MP3 and WAV, as well as applying narration to a video. It is not limited to exporting a finished video.
TTS Lines exports individual MP3 clips, a ZIP of those clips, or a joined MP3 or WAV. Its SRT uses the generated line durations and pauses. A ZIP is useful when each shot needs its own narration. A joined file is simpler for reviewing a complete read.
After moving or trimming narration in your video editor, check captions again. The SRT follows the audio exported from TTS Lines; it cannot follow later timeline changes. Listen for a cut-off word at each edit and watch the finished video once with captions enabled.
Free access and local generation
The free local voices in TTS Lines run on your device after the model downloads. You can generate and export without an account. The script is not sent to a speech API in that local workflow. Loading the website and downloading model files still use the network.
That first download takes time and memory. Generation speed depends on the device, and pronunciation needs checking. The advertised $15/month Pro offer is planned; checkout is not available at the time of this comparison.
CapCut advertises free speech generation. Check the selected voice and final export in your own account before committing a project; this comparison does not establish availability or pricing for every voice, region, or version. It also does not establish that CapCut processes speech locally.
Try one scene before moving the whole script
Use the same short passage in both tools, including a name or technical term you need to say. Listen for the intended pronunciation, then change one sentence. Check how easily you can get the revised audio into the actual video project.
Choose based on that handoff. Stay in CapCut if making the voice beside the picture saves you work. Use TTS Lines if local generation and separate, replaceable narration clips fit your edit. Neither choice establishes a voice-quality or speed winner without a matched listening and timing test.