Read text aloud

Read the text aloud

Click the Listen button in the input area. When you hover over it, the button shows the estimated time, for example “Read aloud (about 5–10 seconds)”.

Text length	Estimated time
Up to 20 characters	5–10 seconds
21–50 characters	10–20 seconds
51–100 characters	20–30 seconds
More than 100 characters	30–60 seconds

In the word details panel, click Play pronunciation to read only the selected word.

Choose a speech engine

Open Voice settings in the input area and choose an option under Speech engine:

Edge TTS (default)
Gemini TTS

Works out of the box with no API key.

Setting	Options
Voice	Female (Nanami): `ja-JP-NanamiNeural` Male: `ja-JP-KeitaNeural`
Speed	From -100 to +100 in steps of 10. The interface shows the value as Very slow, Slow, Normal, Fast, or Very fast.

Uses the gemini-3.1-flash-tts-preview model and requires a Gemini API key. It works if the server has GEMINI_API_KEY configured, or if you entered a Gemini key in Settings.

Voice	Style
Kore	Firm
Puck	Upbeat
Zephyr	Bright
Aoede	Breezy
Leda	Youthful
Charon	Informative

Speaking style options:

Natural: The default style.
Slow: Slows down the speech, which helps with shadowing practice.
Clear: Pronounces words more clearly.

Your speech engine, voice, speed, and style are saved in the current browser and restored automatically the next time you open the app.

When text-to-speech fails

Message	Fix
Enter some text first	The input box is empty. Enter the Japanese you want to hear first.
No API key provided	You’re using Gemini TTS without a usable Gemini key. Enter a key, or switch back to Edge TTS.
The upstream TTS request timed out. Please try again later.	The speech service didn’t respond within 60 seconds. Shorten the text and try again.
Edge TTS request failed (HTTP status code)	The Edge TTS speech API returned an error. Try again later, or switch to Gemini TTS.
Edge TTS returned empty audio	The speech service returned no audio. Try again later, or switch to Gemini TTS.

Edge TTS requests are forwarded through the app server to the speech API api.howen.ink, provided by the project author. If you don’t want your text sent to that service, use Gemini TTS instead. For details, see Keys and privacy.

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Read the text aloud

Choose a speech engine

When text-to-speech fails

​Read the text aloud

​Choose a speech engine

​When text-to-speech fails

Read the text aloud

Choose a speech engine

When text-to-speech fails