[2026 Version] How to Convert Text to Speech? A Thorough Comparison of 7 Speech Synthesis Sites and Software!

In this article,

• I want to create narrations for videos
• I want to improve website accessibility
• I want to play announcements in a store

we will introduce recommended sites and software for those who want to use text-to-speech conveniently for various purposes!

By using text-to-speech sites or software, it is possible to easily convert text into audio.

Since you can synthesize natural-sounding audio that sounds just like a person speaking, why not try some of the recommended sites and software?

7 Recommended Text-to-Speech Sites and Software

Here are the recommended sites and software for converting text to speech!

1. Ondoku
2. VOICEVOX
3. COEIROINK
4. Bouyomi-chan
5. A.I.VOICE
6. AITalk
7. CeVIO

1. Ondoku | Recommended free site for text-to-speech using the latest AI (Commercial use OK)

Ondoku is a recommended web service for converting text to speech.

It is a service used from a website, and you can use it immediately without the need for troublesome installation work.

Ondoku can be used for free.

Moreover, no registration or login is required, and you can use it directly from the top page.

Using the latest AI, you can convert text to speech with high precision and no unnatural feel.

What are the benefits of Ondoku [Free]?

Can be used for free

Ondoku can be used for free with no registration or login required!

It is easy to use; you can convert up to 1,000 characters per month entered into the text box on the top page into audio.

Furthermore, by registering your email address, you will be able to convert up to 5,000 characters per month for free.

Commercial use possible

Of course, commercial use is OK with Ondoku!

With paid plans, credit notation is no longer required (click here for more details on commercial use).

Easy-to-use web service with no installation required

Ondoku is a service utilized from a website.

Therefore, there is absolutely no need for the hassle of installation.

Text-to-speech software often tends to have large download sizes.

In that regard, with Ondoku, you can convert text to speech as soon as you want to use it.

Of course, it can be used in any environment, including PC, iPhone, Android smartphone, or tablet.

A wide variety of voices easy to use for work

In Ondoku, for Japanese, you can choose from 16 types of voices.

Since it has one of the largest variations of voices among tools that can be used for free, it can handle a wide range of situations from personal use to corporate use.

Famous companies also use it, and you can check its track record in the Ondoku case studies.

A key point is that compared to other free tools, it has many voices that are easy to use for business purposes.

Because the character traits aren't too strong, you can synthesize audio that fits into any situation.

Natural reading voice using the latest AI

Ondoku is a reading service that uses the latest AI speech synthesis engine.

It can convert text to speech very naturally.

Of course, speaking speed and voice pitch can also be adjusted freely.

You can check the high quality of the reading for free here, so why not experience Ondoku for yourself first?

Can create dialogues with multiple voices

With Ondoku, you can convert text to speech using multiple voices.

In this way, the text can be read out as if multiple voices are having a conversation.

Can convert foreign languages to speech

Ondoku can convert 48 types of languages into audio, including Japanese!

If you want to convert foreign languages to speech for free, Ondoku is the way to go!

Comfortable to use even with low PC specs

Ondoku is a text-to-speech service that synthesizes audio on a website.

Because the actual processing is performed on the Internet, you can smoothly convert text to speech even if your PC specs are low.

Since speech synthesis software that you install and use requires a certain level of PC specs, this is a major benefit.

If you want to convert text to speech right now, Ondoku is recommended.

For those looking for a way to convert text to speech, why not try using Ondoku for free first?

2. VOICEVOX | Convert text to speech with popular characters like Zundamon

VOICEVOX is a standard text-to-speech and speech synthesis software for converting text to speech.

It is software that you install and use, compatible with Windows, Mac, and Linux.

A feature is that characters are prepared for each type of voice.

Aren't there characters you've seen on the internet, such as "Zundamon" inspired by the Tohoku region, or "Kasukabe Tsumugi," a high school girl from Saitama?

Benefits of VOICEVOX

Intonation can be edited

The VOICEVOX software includes an intonation editing function.

If you want to convert text to speech more realistically, you can fine-tune the audio in detail.

In addition, you can specify audio speed, inflection, etc., in detail.

Can create dialogues with multiple characters

It is also possible to convert text to speech using multiple characters simultaneously.

Can be used for free

VOICEVOX allows you to convert text to speech for free.

Commercial use is also possible (however, you must follow the commercial use terms for each character).

Disadvantages of VOICEVOX

Strong character personality may make it difficult to use for business purposes

The biggest disadvantage of VOICEVOX is that the character personality of the voices is very strong.

When voices are attached to characters, depending on the purpose of converting text to speech, the character's impression might be too strong, making it difficult to use.

When using it to convert text to speech for work, it is recommended to choose characters that are not used very often on video sites like YouTube.

Terms of use differ for each character

Aside from the terms of use for VOICEVOX itself, terms of use for each character also exist.

It is a bit troublesome because you need to check each character every time.

Please note that if you use it for commercial purposes without credit notation, usage fees may apply.

(Example: Zundamon, Shikoku Metan, Kyushu Sora, and Zhongguo Usagi sound sources cost 400,000 yen + consumption tax per character)

Large download size

Another disadvantage is that the download size is large, and depending on the environment, installation can take time.

This is because all voices (voice tones) are installed at the time of installation.

Since a file download of 1GB or more is required for the initial installation, if your internet connection is not fast, or if you are using a wireless connection instead of an optical fiber line, the installation will take quite a while.

Usability depends on PC specs

Since VOICEVOX is software that you install and use on your PC, the speed of speech synthesis depends on your PC specs.

To use the "GPU mode" comfortably, a high-spec PC equipped with a GPU (graphics card) is required.

Foreign languages not supported

Because VOICEVOX was developed for Japanese, it can only convert Japanese text to speech.

VOICEVOX is also explained in this article.

3. COEIROINK | Recommended AI software for converting creative works to speech

COEIROINK is reading software produced with a primary target of being used in creative works.

It is software that you install and use, compatible with Windows, Mac, and Linux.

Credit notation is required when using it.

Benefits of COEIROINK

Attractive and diverse characters can be selected

Official and officially recognized characters are very high quality and attractive in both voice and illustration.

Attractive characters are also set for each of the voices published by users.

Commercial use possible

COEIROINK is available for commercial use.

However, credit notation is mandatory for both commercial and non-commercial use.

Comprehensive editing functions

Although it takes time and effort, the editing functions for accent and intonation are also comprehensive.

Can create original synthesized voices

COEIROINK has a function to create and publish original synthesized voices called "MYCOE."

It is also possible to create audio materials based on your own voice.

Disadvantages of COEIROINK

Character impression is very strong

Just like VOICEVOX, a disadvantage is that the character's impression is very strong.

When converting text to speech for work or business purposes, you might find it difficult to use.

Terms of use are somewhat complex

Aside from the terms of use for COEIROINK itself, please note that the range of available use for each character is determined individually.

There may also be terms of use set for voices created by users other than official or officially recognized characters.

Conversely, depending on the character, purposes prohibited by other speech synthesis services/software, such as "use in adult works," may be permitted.

Large download size

Like VOICEVOX, the download size for COEIROINK is also large.

Since it is necessary to download a file of about 2GB when installing for the first time, it can take quite a while depending on the internet connection.

Installation takes time and effort

Installing COEIROINK requires a certain level of PC knowledge.

It is necessary to perform tasks such as downloading and unzipping multiple files and placing them in folders.

Usability depends on PC specs

Like VOICEVOX, because COEIROINK is software that you install and use, its usability depends on your PC specs.

A high-performance PC equipped with a GPU (graphics card) is recommended to use it comfortably.

COEIROINK is also explained in detail in this article.

4. Bouyomi-chan | Convert text to speech with Yukkuri voices (Commercial use OK)

Bouyomi-chan is reading software compatible with Windows.

It is software that uses "AquesTalk," a long-existing speech synthesis library, and can read text in a unique voice, although it is not realistic.

Benefits of Bouyomi-chan

Very lightweight operation

As you'd expect from software that has been around for a long time, its operation is very lightweight.

You can convert text to speech without issues even on a PC with low specs.

Small download size

The file size is also very small, only about 1.5MB, so it can be downloaded immediately.

Easy operation

The operation screen is very simple.

Even so, minimum adjustment functions such as speed and pitch are firmly provided.

Commercial use possible

Because Bouyomi-chan uses an older version of "AquesTalk" that can be used free of charge regardless of whether it is for-profit or non-profit, commercial use is also possible.

Comprehensive linkage functions

Functions to link with other software to read displayed content, such as a function to read the clipboard (copied text) and a function to read Twitter posts, are comprehensive.

Advanced usage, such as having content read from other software, is also possible.

Disadvantages of Bouyomi-chan

Lacks realism

Because Bouyomi-chan is older-generation speech synthesis software, it lacks realism.

The voices that can be selected are all traditional synthetic voices.

Since it is used in a characteristic way in online videos, including so-called "Yukkuri videos," an unnatural feeling will arise unless you are careful about the situation in which it is used.

5. A.I.VOICE / A.I.VOICE2 | Convert text to speech with popular character voices

A.I.VOICE is speech synthesis software developed by AI Inc.

It uses the AITalk speech synthesis engine.

Software that succeeds VOICEROID and VOICEROID+, for which support has ended, is also being developed as A.I.VOICE.

As of 2026, the A.I.VOICE2 series is being developed.

Benefits of A.I.VOICE

Easy-to-understand one-time purchase model

A.I.VOICE is sold as one-time purchase software.

Once purchased, there are no additional monthly fees.

Attractive characters

Many attractive characters are available, including those inherited from VOICEROID.

There are also many standard characters for Boiro gameplay and Boiro videos, such as Kotoha Akane/Aoi and Yuzuki Yukari.

Commercial use possible depending on the license

By purchasing an individual commercial license or a corporate license, commercial use is also possible.

High functionality unique to paid software

The editing and tuning functions necessary for converting text to speech, such as speed, pitch, and inflection, are of course included and easy to use.

Disadvantages of A.I.VOICE

Expensive for personal software

While it is high-functioning and high-performance, the price is relatively high for personal software.

May be difficult to use for business purposes

While A.I.VOICE for individuals has many attractive characters, for business purposes, the strong character personality can be a disadvantage.

The speech synthesis engine used, AITalk, is very high-performance, so if you want to use it for business purposes, it is also recommended to use AITalk for corporations, which will be introduced next.

The A.I.VOICE series is also introduced in detail in this article.

6. AITalk | Text-to-speech software for corporations (Commercial use OK)

Speech synthesis software using the AITalk speech synthesis engine is also sold as a product for corporations.

Benefits of AITalk

Responds to various operations

AITalk offers products in a wide range of fields, including narration, guidance, chat assistants, and accessibility improvement.

Since it responds meticulously to situations where you want to convert text to speech for business purposes, it is ideal for introduction into operations.

Disadvantages of AITalk

Price is high

Prices are high, partly because it is a product for corporations.

For example, in the case of the narration creation software "AITalk Koe no Shokunin," the base fee is 50,000 yen per month (tax excluded).

7. CeVIO | Convert text to speech with high-quality character voices

CeVIO is reading software that uses a speech synthesis engine developed by Techno-Speech, a venture company from the Nagoya Institute of Technology.

Benefits of CeVIO

Easy-to-understand one-time purchase model

The license for CeVIO is a one-time purchase, and no monthly fees are required.

No additional cost for commercial use by individual creators

No additional costs are required for use by individual creators, such as posting to video sites, distributing works, or at club events and concerts.

It can also be used for educational purposes without additional costs.

Additional estimates are required when using it in corporations or stores, or when used for work under contract.

Attractive characters

Attractive characters are also available for CeVIO.

Realistic pronunciation using deep learning

Unlike other speech synthesis software, CeVIO reproduces audio using AI technologies such as deep learning.

As a result, it is possible to convert text to speech more realistically.

Disadvantages of CeVIO

Strong character personality may be a negative

Like other speech synthesis software, it is a product with strong character personality, so it might be difficult to use for business purposes.

Price is relatively high for personal software

While the performance for converting text to speech is very high, the price is relatively high for personal software accordingly.

Why not try converting text to speech with recommended sites and software?

In this article, we introduced sites and software for synthesizing audio.

Japanese speech synthesis is particularly well-served with sites and software.

Since there are a wide range of options from personal use to business use, why not try some of the recommended sites and software according to your purpose?

■ 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.