[For AI Beginners] 2 Free AI Voice Synthesis Tools | The Era of 'Speaking Like a Human' is Here! | TTS
2026/6/8 Added to related articles: 'If you have a gaming PC, voice cloning is the most recommended'.
2 Natural TTS Tools You Can Use for Free
AI voice synthesis (Text to Speech / TTS) has evolved significantly over the past few years, and it is now capable of quite natural emotional expression.
It is not just 'reading aloud', but rather approaching narration that sounds like a person speaking is a major feature.
This time, I will introduce two representative AI voice synthesis tools that you can use for free.
① VOICEVOX
The first one is VOICEVOX, which is very widely used in Japan.
If you watch YouTube, you may have heard it at least once.
For example:
“Zundamon” (Zunda Mochi spirit) often adds 'nanoda' to the end of sentences Voice:
VOICEVOX: Zundamon, there are things that are surprisingly not well known.
“Aoyama Ryusei”: Narration voice often used in trivia and commentary short videos (often used in combination with BGM 'Escort')
Voice: VOICEVOX: Aoyama Ryusei
BGM: Escort written by MoppySound
It is used in various types of content.
■ Features
Choose from many character voices
Rich variety of voices
Available for free
■ About emotional expression
Some voices allow you to adjust emotional parameters, but overall, compared to other AI voices, there are parts where the expressiveness feels a bit modest (this is my personal impression).
Also, there are quite a few misreadings of kanji.
Example) That person (achira no kata) -> achira no hou
However, it can be used in a local environment, and its major strengths are that it is stable, easy to use, and beginner-friendly.
Also, when using it, credit must be given according to the license of each voice actor, so please be aware of that point.
② Google AI Voice (Google Speech / AI Studio)
The second one is Google's voice synthesis.
Google AI Studio and other tools can be used to access it.
Example of Google Speech (LTX-2.3 is amazing)
■ Features
Basically available for free (with daily usage limits)
Very natural emotional expression
Reads by understanding the meaning of the text
A particularly major feature is that it adds natural intonation and emotion according to the context without needing detailed settings.
Therefore, creating narration becomes very easy.
■ Points to note (based on actual usage)
On the other hand, there are some points to note in actual operation.
Even if you choose the same speaker (voice actor), the tone of the voice may change with each generation
Voice quality may not be consistent when generated in segments
Volume may gradually change in long sentences
For this reason, basically,
you need to create your script with the premise of 'generating it all at once from start to finish'.
Also, adjusting the volume with video editing software after generation is often done.
Still, I have been using this Google voice a lot recently.
The reason is simple: the naturalness of the emotional expression is extremely high.
■ Summary
AI voice synthesis has already surpassed the practical level, and is evolving from 'mechanical reading' to '
natural conversational speech'.
Especially recently, the accuracy of emotional expression has improved significantly, and an environment has been established where even individuals can create high-quality narration videos.
In the future, it is expected to evolve further into technology that reproduces more realistic voices and individual voices.