The Vietnamese voices
- Free: Bảo Trâm (female) and Thế An (male), both with a Southern accent. The same group has 14 more voices in English, Mandarin, Japanese, Korean, Thai, French and Spanish.
- Plus: 182 Vietnamese voices with Northern, Central and Southern accents, among about 2,600 voices in 7 languages.
- You do not need voice names. Ask Claude to “find a northern Vietnamese female Plus voice”, and it searches and lists them for you to choose.
- Reading speed goes from 0.5 to 2 times.
Add it to Claude
- Open the AI assistants page Sign in to Yangopen, go to AI assistants (MCP), choose Claude and click Add YangOpen to Claude.
- Connect your account In Claude, click Add. The first time Claude uses YangOpen, click Connect in the chat, sign in to Yangopen and click Allow. You do this once.
- Try one line Send Claude: “Read my shop's welcome line in Bảo Trâm's voice.”
- Claude Code: run claude mcp add --transport http --scope user yangopen https://yangopen.com/mcp, restart Claude Code, and when it asks for a sign-in, type /mcp and choose yangopen › Authenticate.
- The full setup, including Claude accounts in an organization: Claude MCP connector.
Long text and waiting time
- A free voice reads up to 3,000 characters per call. A Vietnamese Plus voice reads up to 1,000, other languages 400.
- Longer text: Claude cuts it at sentence ends and calls again. Each part is its own MP3 file.
- Plus voices run on Yangopen's own server: about 30–40 seconds for 1,000 characters of Vietnamese (measured on 22 October 2026).
Cost and your data
- Free voices cost no credit; they count against the account's free daily allowance: 200,000 characters at the time of writing.
- Plus voices: 25 credits per 1,000 characters, charged only when the MP3 is ready. The answer states the credits charged and the balance. A new account gets 500 credits, enough for 20,000 Plus characters. Current prices are on the pricing page.
- The text is not stored. The MP3 is kept for 24 hours, then deleted.
- Free voices send the text to an outside speech service. Plus voices run on Yangopen's server.
For developers
A remote MCP server over Streamable HTTP at https://yangopen.com/mcp. Every tool call needs an OAuth sign-in; the handshake (initialize) and tools/list do not. Its name in the official MCP Registry: com.yangopen/mcp.
- list_voices: search voices by language, gender, or words in the name or style.
- text_to_speech: read with a free voice and return an MP3 link.
- text_to_speech_plus: read with a Plus voice, using credits.
- get_balance: the credit balance and how many Plus characters it buys.
When to use the tool page instead
- Background music, an M4A or WAV file, or SRT subtitles: use the Text to speech page. The connector returns MP3 only.
- No account yet: the tool page reads with the free voices without signing in. The connector always needs a sign-in.
Frequently asked questions
Is there an MCP server for Vietnamese text to speech?
Yes. Add https://yangopen.com/mcp as a custom connector in Claude, sign in to Yangopen once, then ask Claude to read your text. The result is an MP3 link.
Are there Northern Vietnamese voices?
Yes, among the Plus voices: 182 Vietnamese voices with Northern, Central and Southern accents. The two free Vietnamese voices both have a Southern accent.
Is it free?
Yes, with the Bảo Trâm and Thế An voices: no credit, within the account's free daily allowance. Plus voices cost 25 credits per 1,000 characters.
Can it read long text?
Yes. Claude cuts the text at sentence ends and reads each part: up to 3,000 characters per part with a free voice, 1,000 with a Vietnamese Plus voice. Each part is one MP3 file.
Does it work with other AI assistants?
Any assistant that can add a remote (HTTP) MCP server and supports MCP sign-in (OAuth) can use https://yangopen.com/mcp.
Updated: