[Summary] A Comparison of Which Text-to-Speech Software Reads Sentences or Text Most Naturally

Hello, thank you for always using Ondoku.

What is the most important thing you look for when searching for text-to-speech software?

1. Whether it is free or paid
2. Whether it reads in a human-like way
3. Whether the speed and pitch can be adjusted

These are the three main areas of concern.

In particular, "whether it reads in a human-like way" is a very important issue for those listening to the audio.

The text-to-speech software industry continues to evolve rapidly.

This time,

• Sites that support Japanese
• Adjustments are possible

Based on these conditions, we investigated which text-to-speech software reads most naturally like a human.

*Note: This article contains old content. You can listen to the latest voice samples in this article, so please check it out as well!

Listen to 16 types of Ondoku text-to-speech voices for free. Change the impression by varying the pitch | Text-to-speech software Ondoku

Ondoku has 16 types of Japanese voices. Of course, both male and female voices are available. We have made it possible to listen to 8 commonly used Japanese voices and what they sound like when their pitch is adjusted.

Famous Text-to-Speech Software

When you research text-to-speech software, you will find that there are many available.

However, upon further investigation, it is quite common to find cases where the software is different, but the internal speech synthesis engine is the same.

Ex) Bouyomi-chan and SoftTalk use the same speech synthesis engine.

Since the audio quality is the same if the speech synthesis engine is the same, this investigation treats different software as the same if they use the same engine.

Paid Text-to-Speech Software

• AI Talk
• VOICEROID
• Ichitaro (Word processing software)

Free Text-to-Speech Software

• TextTalk
• SoftTalk
• Bouyomi-chan
• Coestation
• Ondoku

Standards for Human-likeness in Text-to-Speech Software

The standard for what constitutes a human-like voice varies from person to person.

• Whether it reads with rich emotion
• Whether it speaks with proper pauses and intonation
• Whether it includes exclamations or breathing sounds

Everyone has their own standard for what kind of voice feels like a human speaking when reading text aloud.

For this comparison, we will place importance on the standard of human-like reading as:

being able to read smoothly with appropriate pauses and without unnatural intonation.

This is because the function to read with emotion was (as of 2021 when this article was written) only available in paid text-to-speech software.

Since we want to include free software in the comparison, let's compare them based on this standard.

Manuscript for Comparison

To make a comparison, it is necessary to have the text-to-speech software read a manuscript.

Since there are several software options, we used a short manuscript of a weather forecast, which does not feel unnatural even without emotion.

Here is the national weather forecast.
On the Pacific side, including Tokyo, dry and sunny weather will continue.
Please be sure to take precautions against catching a cold.
Here are the temperatures from noon to night.
Nationwide, typical January cold will likely continue.

Actual Comparison of Read-Aloud Voices

Now, let's have the text-to-speech software actually read it.

You can play the actual audio by clicking the play button (▶).

TextTalk

【Under adjustment】

SoftTalk and Bouyomi-chan

Ondoku

Voice Assistant

Announcer A

Announcer B

AI Talk

【Under adjustment】

VOICEROID

【Under adjustment】

Ichitaro (Word processing software)

【Under adjustment】

Coestation was excluded this time because it requires synthesis using your own voice.

Impressions After Listening to the Reading Results

I felt that the text-to-speech software available for free that can read in a human-like way are:

1. Ondoku
2. TextTalk
3. Bouyomi-chan

For TextTalk, the high-pitched metallic sound is noticeable,

for Bouyomi-chan, the muffled voice is noticeable, so preferences may vary.

Among those available for a fee:

1. VOICEROID
2. AI Talk

followed this order in terms of the impression of being able to read more like a human.

Also, some paid versions are equipped with functions to add emotion and intonation to the voice.

Having these options would likely broaden the range of audio usage even further.

Which software you use depends on your preference.

If you are considering commercial use, we have also summarized the commercial use policies for each software, so please refer to this article as well.

[Paid Version] What are the commercial use licenses for text-to-speech software? We investigated usage on YouTube | Text-to-speech software Ondoku

We will introduce whether commercial use is possible for four types of paid text-to-speech software and what their licenses are. The software we will cover this time are Ondoku, AI Talk, VOICEROID, CeVIO, and Yukkuri-style voices (AquesTalk2).

We look forward to seeing you.

■ AI voice synthesis software "Ondoku"

"Ondoku" is an online text-to-speech tool that can be used with no initial costs.

• Supports approximately 50 languages, including Japanese, English, Chinese, Korean, Spanish, French, and German
• Available from both PC and smartphone
• Suitable for business, education, entertainment, etc.
• No installation required, can be used immediately from your browser
• Supports reading from images

To use it, simply enter text or upload a file on the site. A natural-sounding audio file will be generated within seconds. You can use voice synthesis up to 5,000 characters for free, so please give it a try.

Text-to-speech software "Ondoku" can read out 5000 characters every month with AI voice for free. You can easily download MP3s and commercial use is also possible. If you sign up for free, you can convert up to 5,000 characters per month for free from text to speech. Try Ondoku now.

HP: ondoku3.com
Email: ondoku3.com@gmail.com