Text to speech API: turn text into an audio file (MeloTTS)

$0.01 per call · failed calls are never charged · no account needed: a card key or USDC

Turn up to 300 characters of text into natural, human-sounding speech as an MP3 (base64), in English (40 voices) or Spanish (10 voices), with Deepgram Aura-2. Pick a voice by name or leave the default. Use for voice replies, audio notes, accessibility and phone or chat bots; for up to 2,000 characters use text_to_speech.

When to use it

Voice replies, audio notes, accessibility and phone or chat bots
Speak up to 1,000 characters in English, Spanish, French, Chinese, Japanese or Korean

Buy credits by card (from $1) Example result (JSON)

Inputs

Name	Type	Description
`text` (required)	string	Text to speak, up to 300 characters
`lang`	string	Language: en or es (default en). One of: `en`, `es`.
`voice`	string	Voice name. English: amalthea, andromeda, apollo, arcas, aries, asteria, athena, atlas, aurora, callista, cora, cordelia, delia, draco, electra, harmonia, helena, hera, hermes, hyperion, iris, janus, juno, jupiter, luna, mars, minerva, neptune, odysseus, ophelia, orion, orpheus, pandora, phoebe, pluto, saturn, thalia, theia, vesta, zeus. Spanish: sirio, nestor, carina, celeste, alvaro, diana, aquila, selena, estrella, javier. Default: luna (en), aquila (es)

Request

Over HTTP, with a card key from /credits:

curl -H "Authorization: Bearer adt_…" "https://glyphcall.com/ai/speech?text=Your%20payment%20was%20received.%20Thank%20you!"

Without a key, the same URL answers 402 Payment Required with x402 and MPP terms, so an agent with a wallet pays per call in USDC (Base, Polygon, Arbitrum or Solana over x402; Base or Tempo over MPP) and retries.

Example result

{
  "contentType": "audio/mpeg",
  "audioBase64": "SUQzBAAAAAAAI1RTU0UAAAAPAAADTGF2ZjYwLjMuMTAwAAAA…",
  "bytes": 41472,
  "lang": "en",
  "voice": "luna",
  "characters": 37,
  "model": "@cf/deepgram/aura-2-en"
}

From an AI agent (MCP)

Add the MCP server to Claude, Cursor or any MCP client. This tool is ai_speech, and the first 25 successful calls are free:

https://glyphcall.com/mcp

Questions

What do I get back?

The audio as base64 with its content type and size in bytes.

How do I pay?

Each successful call costs $0.01; failed calls are not charged. This tool is not in the free calls; pay with card credits (from $1; the key goes in an Authorization header or, for clients that can only fetch a URL, as api_key= in the URL) or per call in USDC over x402 or MPP. No account is needed.