10 Best AI Voice Generators in 2026: Free and Paid Comparison

I want to know about recommended AI speech synthesis software!

AI speech synthesis software that converts text into natural speech is gaining more and more attention right now!

With advancements in AI technology, the quality of speech synthesis software has improved dramatically.

It can generate natural, human-like speech with high quality that is incomparable to the mechanical reading of the past.

The flow for getting started and the operating environment differ between web app types that can be used for free and desktop types that are installed on a computer.

In addition to products using AI, there are also products that use conventional speech synthesis engines such as AquesTalk and OpenJTalk.

In this article, we compare 10 of the latest speech synthesis software products for 2026 based on differences in types and functions!

Things you want to check when choosing are whether it is a web app or desktop type, whether it works locally, how much you can adjust the voice, speed, and intonation, and whether you can use character voices.

We will explain each difference in detail, so why not find the perfect speech synthesis software for you?

【Free】Recommended AI speech synthesis software you can use right now

If you are looking for speech synthesis software, Ondoku is recommended!

Ondoku is speech synthesis software using the latest AI technology, available for free from your browser.

Its features include the ability to easily synthesize high-quality speech right now without installation on any environment—PC, iPhone/iPad (iOS), or Android smartphone.

Even though it is free, it can read up to 5,000 characters and commercial use is also OK!

It supports multiple languages such as English, Korean, and Chinese in addition to Japanese, so you can easily create audio in foreign languages.

If you are unsure about speech synthesis software, why not try Ondoku for free first?

What is speech synthesis software? Basic knowledge explained for beginners

First, we will briefly explain the types of speech synthesis software and the functions you should check when choosing.

Differences between AI reading and conventional speech synthesis methods

Speech synthesis software refers to software that automatically converts input text into speech.

Speech synthesis software includes methods that use AI and methods that use conventional speech synthesis engines such as AquesTalk and OpenJTalk.

Previous speech synthesis software had mechanical vocalizations and felt very unnatural.

However, now, thanks to the latest AI technology, natural intonation and pausing like a human have become possible.

In particular, speech synthesis software that utilizes deep learning allows for realistic and easy-to-understand expressions, much like professional voice actors or narrators.

Fine customization, such as adjusting the reading speed and changing the pitch, is also possible.

Differences between web app types and desktop types

Speech synthesis software includes web app types used from a browser and desktop types installed on a computer.

The appeal of web app type speech synthesis software used from a browser is that it can be used immediately without installation.

With the AI web app Ondoku, you can utilize the latest AI technology regardless of your PC's performance.

Desktop types are installed and used on a computer.

Installation-type speech synthesis software has the advantage of being usable even in offline environments.

When choosing, in addition to whether it is a web app or desktop type and whether it uses an AI or conventional method, it is recommended to check the voice types, adjustments for speed, pitch, and intonation, and support for character voices.

【Free available】Comparison of 10 speech synthesis software products for 2026 by type and function

We compare 10 products based on whether they are used from a browser or installed on a computer, whether they use an AI method or a conventional engine, how much the voice, speed, and intonation can be adjusted, and whether character voices can be used.

If you want to use it locally, check the compatible OS and offline usage conditions for each product.

1. Ondoku | Free speech synthesis software with latest AI reading

Ondoku is a high-quality speech synthesis software that adopts the latest AI technology.

If you are looking for speech synthesis software, this is the first option you should try!

As a web app type software that can be used from a browser, no troublesome installation work is required.

Just enter text and press a button, and you can synthesize natural audio files in just a few seconds.

Japanese voices can be selected from more than 16 options, with a rich variety including female voices, male voices, and children's voices.

Listen to 16 types of voices from the text-to-speech software Ondoku for free. Change the impression with pitch changes

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 the sounds when the pitch of each voice is adjusted.

Since it supports multiple languages, speech synthesis for foreign languages such as English, Chinese, and Korean is also easy.

Reading speed and pitch can be adjusted freely, so you can create the optimal audio for your purpose.

Since commercial use is also OK, it is ideal for YouTube monetization and business use (Click here for details on commercial use).

And Ondoku is free!

It can be used without registration or login, so it is recommended to actually try speech synthesis with the latest AI first.

Why don't you try using Ondoku for free too?

2. VOICEVOX | Speech synthesis software with popular characters like Zundamon

VOICEVOX is a desktop speech synthesis software compatible with Windows, Mac, and Linux.

The biggest feature is the ability to read aloud with popular character voices such as "Zundamon," "Shikoku Metan," and "Kasukabe Tsumugi."

It uses deep learning technology and allows for fine adjustments of the audio.

The software itself is free and commercial use is possible, but care is required as the terms of use differ for each character.

A GPU-compatible version is also provided, allowing for faster processing on high-performance PCs.

Complete Guide to using VOICEVOX! Detailed explanation from features of the free AI speech synthesis software to commercial use

A detailed explanation from the features of VOICEVOX to its usage and precautions for commercial use. A complete guide to the free AI speech synthesis software that can read aloud with popular character voices like Zundamon.

3. Bouyomi-chan | Speech synthesis software compatible with Yukkuri voice for streaming

Bouyomi-chan is a speech synthesis software widely used in game and live streaming.

It can synthesize speech with the characteristic voice known as "Yukkuri voice."

Coordination functions with streaming software like OBS are also extensive, making it ideal for reading YouTube or Twitch comments aloud.

It is also used as a staple for "Yukkuri Let's Play" and "Yukkuri Commentary" on Nico Nico Douga and YouTube.

It is a lightweight free software for Windows that operates comfortably even on low-spec PCs.

Because it uses older versions of AquesTalk, commercial use is possible even for free.

The sound quality is mechanical, but it is a speech synthesis software whose unique personality is loved by many creators.

4. SofTalk | Simple speech synthesis software with a long history

SofTalk is a simple free speech synthesis software for Windows.

With a simple interface specialized in basic functions, even beginners can use it easily.

Since multiple speech synthesis engines can be selected, you can choose the audio according to the application.

*Note: It previously supported "Yukkuri voice," but it is currently unsupported.

The software itself is free, but to use it commercially, you need to check the terms of the audio engine being used.

It is a free software ideal for those seeking basic speech synthesis functions.

5. COEIROINK | AI speech synthesis software for creative activities

COEIROINK is an AI speech synthesis software developed for creative activities.

It is a desktop type compatible with Windows, Mac, and Linux, and can read aloud with various character voices.

In addition to official and approved characters, user-created voice models "MYCOE" can also be used.

Commercial use is also possible, but credit notation is mandatory.

Also, since terms of use differ for each voice model, confirmation before use is important.

This speech synthesis software is suitable for those seeking unique voices for creative purposes.

What is COEIROINK? Thorough explanation of the features, usage, and commercial use of the speech synthesis software

A complete guide to the features and usage of COEIROINK. We explain in detail everything from how to install the speech synthesis software to adding character voices and precautions for commercial use.

6. Textalk | Lightweight speech synthesis software for Windows

Textalk is a lightweight and simple free speech synthesis software for Windows.

It uses OpenJTalk and the standard Windows speech synthesis engine.

While the naturalness of the voice has its limits compared to the latest AI, it has sufficient performance for basic reading.

It is a software that can be used just by unzipping the ZIP file, and it operates comfortably even on old PCs or low-spec environments.

7. Yukumo! | Speech synthesis software that allows using Yukkuri voice from a browser

Yukumo! is a web app type speech synthesis software that allows you to use "Yukkuri voice" from a browser.

No installation is required, and it can be used from any device.

It supports multiple versions such as AquesTalk1, AquesTalk2, and AquesTalk10.

This speech synthesis software is recommended for those who want to start "Yukkuri Commentary" or "Yukkuri Let's Play" without installation.

8. A.I.VOICE | Paid speech synthesis software supporting popular characters from VOICEROID

A.I.VOICE is a high-quality paid speech synthesis software developed by AI Inc.

It is the successor product to VOICEROID, and A.I.VOICE2 is currently being rolled out.

The biggest feature is the lineup of popular character voices such as "Yuzuki Yukari" and "Kotoha Akane/Aoi."

It is compatible with both Windows and Mac and is sold as a one-time purchase paid speech synthesis software.

Commercial use by individuals is basically possible by purchasing the product, but corporate use requires a separate license.

This speech synthesis software is ideal for creating creative audio works and high-quality narration.

A.I.VOICE2 Complete Guide! Detailed explanation of the features, installation method, and usage of the VOICEROID successor software

Explaining the features and usage of A.I.VOICE2, where you can use Kotoha Akane/Aoi and Yuzuki Yukari, familiar from VOICEROID videos. Introducing everything from installation methods to audio exporting in detail.

9. CeVIO AI | Expressive paid speech synthesis software with popular characters

CeVIO AI is a speech synthesis software that combines reading and singing functions.

It is sold as a paid speech synthesis software exclusively for Windows.

It is characterized by being able to use unique and popular character voices such as "Sato Sasara" and "Suzuki Tsudumi."

With its original speech synthesis AI, it can read text with rich emotions.

In addition to "Talk Voice" for reading, "Song Voice" for singing is also available, supporting both reading and singing.

Commercial use conditions for individual creators are relatively loose, but corporate use requires a separate license.

This speech synthesis software is recommended for those who want to create audio content with rich expressiveness.

What is CeVIO AI? Detailed explanation of speech synthesis software features, usage, and commercial use

A complete guide to the AI singing voice synthesis software CeVIO AI. We explain the characteristics of popular characters like Sato Sasara and Suzuki Tsudumi, how to purchase, and precautions for commercial use for beginners.

10. VOICEPEAK | Paid speech synthesis software with a variety of characters

VOICEPEAK is one of the few desktop speech synthesis softwares that supports Windows, Mac, and Linux.

This also allows for speech synthesis with various popular characters.

It is also characterized by packages that bundle multiple character voices, with a rich lineup of not only female voices but also male voices.

Commercial use rights are included in the basic license, but separate terms apply to character voices.

It is ideal for narration production and speech synthesis on multiple platforms.

What is the speech synthesis software VOICEPEAK? Detailed explanation including features and commercial use

Explaining in detail what features the speech synthesis software "VOICEPEAK" has. Also introducing the commercial use terms, which often differ for each character.

【Free】How to use speech synthesis software? Detailed explanation of how to use Ondoku

How do I use speech synthesis software? Is it easy to use?

From here, we will explain how to actually use speech synthesis software, taking Ondoku as an example!

【Free】The flow of reading text with the speech synthesis software Ondoku

If you are going to use speech synthesis software from now on, web app type speech synthesis software that can be used easily without installation is recommended!

To read text with Ondoku, first access the official website.

When you open the top page, there is a text box, so enter the content you want to read aloud.

(Copy-paste is also OK)

Next, select the voice type.

You can listen to the voices available in Ondoku in this article, so please take a look!

Listen to 16 types of voices from the text-to-speech software Ondoku for free. Change the impression with pitch changes

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 the sounds when the pitch of each voice is adjusted.

Then just click or tap the "Read aloud" button!

High-quality audio is completed in just a few seconds.

Since the audio file can be downloaded in MP3 format, it can be utilized for various purposes such as video narration and in-store broadcasts.

In this way, the free speech synthesis software Ondoku is very easy to use.

For those looking for speech synthesis software, why not try using Ondoku first?

Ondoku also allows adjustment of reading speed and pitch

The speech synthesis software Ondoku also supports adjustments for reading speed and pitch!

It is effective to adjust the reading speed according to the importance of the content.

When using it for language study, it is also recommended to boldly lower the speed all at once.

Adjusting the pitch of the voice is also recommended when using it for video narration.

By changing the pitch, you can create a character personality that matches the listener.

What are the advantages and disadvantages of AI speech synthesis software?

When using speech synthesis software, it is also recommended to thoroughly understand the advantages and disadvantages.

We will briefly explain the advantages and disadvantages of AI speech synthesis software.

What are the advantages of AI speech synthesis software?

The biggest advantage of speech synthesis software is reducing costs.

When requesting a professional narrator, many costs such as recording fees, studio fees, and travel expenses are incurred.

However, if you choose a speech synthesis software that can be used commercially for free, you can significantly save on these costs.

Another major advantage is being able to shorten the time spent on audio creation.

Until now, trying to create video narration or in-store broadcasts required a lot of time for booking recordings, re-recording, and editing work.

But with speech synthesis software, audio is completed in just a few seconds just by entering text.

High-quality audio can be created for free at any time

High audio quality is also an advantage of AI speech synthesis software.

When humans read aloud, variations in quality may occur depending on physical condition or mood.

Also, if you record yourself without requesting a professional, the audio can sometimes become very difficult to hear...

In that respect, speech synthesis software can generate audio of the same quality at any time.

There is no need to worry about sound quality deteriorating due to recording equipment or the surrounding environment.

The fact that it can be used 24 hours a day, 365 days a year is also a unique advantage of speech synthesis software.

Even in the middle of the night or early morning, you can create audio immediately when you think of it.

With multilingual speech synthesis software, foreign language narration can also be created easily.

Disadvantages of AI speech synthesis software

There are also some disadvantages to speech synthesis software.

Depending on the software, there may be limits to emotional expression.

If you are dissatisfied with the expression, it is also recommended to try using a speech synthesis software that uses the latest AI for free.

Attention is also required for commercial use.

Since there are paid softwares with restrictions on commercial use, let's check the terms of use in advance.

When you want to use it for video monetization or business, software that can be used commercially for free, starting with Ondoku, is ideal.

What you can do with Ondoku. About commercial use (business use) and prohibited acts.

Commercial use (business use) is possible with Ondoku. Use for the purpose of obtaining monetary or other benefits, directly or indirectly, regardless of whether you are an individual or a corporation, is commercial use. However, please be careful as prohibited acts are established in Ondoku. This time, what you can and cannot do with Ondoku...

How to choose speech synthesis software explained by application

Finally, we will explain in detail the points for choosing software that matches the audio you want to create by application.

How to choose for video production and YouTube narration

When putting narration in video production, check if it can read with a natural voice and whether character voices can be used.

It is important to choose software that allows you to adjust the voice type, reading speed, and pitch to match the content of the video.

Another point is to choose a speech synthesis software that allows commercial use and is compatible with monetization such as YouTube.

With Ondoku's high-performance AI speech synthesis engine, you can create easy-to-hear audio like a professional narrator.

What is important in video production is adjusting the reading speed according to the content.

Setting important parts to be slightly slower is effective.

How to quickly create narration for videos such as YouTube with text-to-speech software. Tips and points

Explaining how to quickly create YouTube video narration with Ondoku. From how to create scripts, how to use Ondoku, adjusting natural intonation, to tips for editing with video editing software, everything is explained in an easy-to-understand manner. A must-see for those who want to streamline video production with text-to-speech software!

How to choose for language learning materials

When making language learning materials, it is recommended to choose software that supports the audio of the language you want to learn.

By using Ondoku, which supports multiple languages, you can accurately study the pronunciation of various languages.

Creating materials for shadowing, which is effective for language learning, is also easy if you have speech synthesis software.

Foreign language listening materials can also be created.

The point when making materials for language learning is to make the playback speed slow at first.

Since Ondoku can lower the playback speed down to 0.3x, it is also ideal for those who have just started studying a foreign language.

【Complete Guide】What is the way to do English shadowing? Also explaining how to make materials that can be done for free!

Efficiently improve your English skills with shadowing! A learning method that improves listening, pronunciation, and speaking at the same time, explained for beginners. Also introducing methods for creating materials with free AI audio.

How to choose when making audio for business use

When using for corporate business purposes, check whether it can be used commercially, whether it can read the necessary languages, and whether it can be used locally.

• Converting presentation materials into audio
• Adding audio to internal training materials
• Guidance audio for call centers
• Announcements within facilities

Speech synthesis software can be utilized for a wide range of applications.

If you use speech synthesis software capable of reading in foreign languages, you can also easily create announcements for inbound tourists in English, Korean, Chinese, etc.

For companies that emphasize security, the service Ondoku, originating from Japan, is safe.

Even when using for business, be careful to use speech synthesis software that supports commercial use.

Realize professional-level in-facility broadcasts with automatic voice! AI announcement complete guide

Automate in-facility broadcasts with AI! With Ondoku, create narrator-level automatic voice for free. Fully prepared for inbound measures with multi-language support. Also contributing to cost reduction through operational efficiency!

Game streaming and live streaming

When using speech synthesis software in live streaming, real-time reading is important.

By linking speech synthesis software specialized for streaming like Bouyomi-chan with OBS, you can check comments without taking your eyes off the screen.

If you utilize the reading function for viewer comments, it is also possible to liven up the streaming content even further.

Improving accessibility

Speech synthesis software is also a very important tool for visually impaired people and those with learning disabilities.

By converting website text into audio, more people will be able to access digital information.

In addition to people with disabilities, usability can also be improved by introducing speech synthesis software in services for the elderly.

When creating audio that is easy for anyone to hear, check whether reading speed and pitch can be adjusted in addition to a natural voice.

With high-quality AI speech synthesis software with a realistic voice, you can create audio that is less tiring even when listening for a long time.

For accessibility compliance for corporate or organizational websites or creating guidance broadcasts for public facilities, the latest AI speech synthesis software is recommended.

How to choose speech synthesis software Summary

With advancements in AI technology, anyone can now easily create high-quality audio with speech synthesis software.

A web app type is recommended for creating audio immediately, and a desktop type that works offline is recommended for use without connecting to the internet.

Even among desktop types, the naturalness of the voice changes significantly depending on whether you choose an AI method or a conventional method.

If you want to check the functions of each software, please take a look at the comparison table introduced in this article.

If you are considering commercial use such as monetization of YouTube, it is also important to check the terms of use carefully and use speech synthesis software that allows commercial use.

With Ondoku, you can easily experience speech synthesis right now for free and without installation.

Why don't you try experiencing a free-to-use speech synthesis software first?