CastReader vs Ondoku (音読さん)
Ondoku Has Character Limits. CastReader Has None.
Ondoku's free tier caps you at 5,000 characters per month. Need more? Pay ¥980/month. CastReader reads unlimited text for free — articles, ebooks, research papers. No character counting.
Feature Comparison
| Feature | CastReader | Ondoku (音読さん) |
|---|---|---|
| Price | Free forever | ¥980/month (free: 5K chars) |
| Voice Quality | 8/10 (Kokoro AI) | 7/10 (cloud API voices) |
| Kindle Cloud Reader | ✓ Works (OCR) | ✗ Fails |
| WeRead Support | ✓ Works | ✗ Fails |
| AI Chat Per-Response | ✓ Listen button per response | ✗ Reads entire page |
| Paragraph Highlighting | Paragraph-level on page | N/A (generates audio file) |
| Page Extraction | 15+ specialized extractors | N/A (paste text) |
| Account Required | ✓ No account needed | Yes |
Why Choose CastReader Over Ondoku (音読さん)
Japanese web-based TTS service with character limits on free tier? Here's what CastReader does differently.
No Limits
Read As Much As You Want
Ondoku's free tier limits you to 5,000 characters per month — about 2 articles. After that, you pay ¥980/month. CastReader has no character limits, no monthly caps, no premium tier. Read 100 articles a day if you want. Free forever.
One Click
No Copy-Paste, No Downloads
Ondoku requires you to copy text, paste it into the website, generate audio, then download the file. CastReader reads any web page with one click — no copying, no file management. The text is read aloud right on the page with paragraph highlighting.
No Account
Start Listening Immediately
Ondoku requires account registration even for the free tier. CastReader requires nothing — install the Chrome extension and start reading. No email, no password, no verification.
Frequently Asked Questions
CastReader vs Ondoku (音読さん) — common questions
Is CastReader better than Ondoku?
For reading web content: yes. CastReader reads any web page with one click, no character limits, no account needed. Ondoku is better if you need to generate audio files for download — CastReader is a reading tool, not an audio file generator.
How many characters can I read with CastReader?
Unlimited. There are no character limits, daily caps, or monthly quotas. Read as much as you want, forever, for free.
Does Ondoku work as a Chrome extension?
No. Ondoku is a website where you paste text to generate audio. CastReader is a Chrome extension that reads any web page directly in your browser.
Can CastReader generate audio files like Ondoku?
CastReader reads text aloud in real-time in your browser. It does not generate downloadable audio files. If you need MP3/WAV files for videos or podcasts, Ondoku or VOICEVOX is a better fit.
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Try CastReader Free
No signup. No limits. Install and start listening in 10 seconds.