Text-to-Speech
Seamless real-time streaming with natural, expressive speech that masters complex pronunciations. Perfect text-audio synchronization through high-precision word-level timestamps.
TEXT TO SPEECH
CAPABILITIES
Full suite of voice AI models to power your agents
Speech-to-Text
Best-in-class accuracy with controllable latency and robust performance in noisy environments. Semantic voice activitydetection that enables smart turn-taking, ensuring human responsiveness.
SPEECH TO TEXT
Voice Cloning
Instant voice cloning from just 10s of audio, or leverage Pro Voice Clones for a fine-tuned model indistinguishable originals. Highest market speaker similarity for truly authentic output.
Built by the pioneers of voice AI
Gradium translates years of peer-reviewed work into production-grade APIs that handle the hard problems: latency, naturalness, and scale.
INFRASTRUCTURE
Infrastructure that enables scale for real-time applications
Built for systems where latency is a requirement, not an optimization. From first integration to production scale, behavior remains predictable.
API
WebSocket APIs designed for streaming. Built for bidirectional, real-time communication.
SDKs & Integrations
Clients in Python and Rust. Integration in all major agent frameworks, including Livekit and Pipecat.
Security & Compliance
Private cloud options available for on prem deployments. Enterprise plans including zero data retention.
Reliability
Stable latency in production up to high concurrency limits. SLA for enterprise plans.
Native fluency across languages
One voice, five languages with consistent pronunciation and prosody across languages. Seamless mid-sentence code-switching without latency.
PRICING
Predictable and scalable pricing
1 character of TTS = 1 credit and 1s of STT = 3 credits
Monthly
Yearly Save 1 month
Free
$0/month
| Credits | 45k |
| Hours of TTS | ~1hr |
| Hours of STT | 3hrs |
| Studio Access | Yes |
| API Access | Yes |
| Max concurrency | 2 |
| Commercial use | No |
| Instant voice clone | 5 |
| Pay as you go | No |
XS
$13/month
| Credits | 225k |
| Hours of TTS | ~5hrs |
| Hours of STT | 13hrs |
| Studio Access | Yes |
| API Access | Yes |
| Max concurrency | 5 |
| Commercial use | Yes |
| Instant voice clone | 1000 |
| Pay as you go | $6.9 |
POPULAR
S
$43/month
| Credits | 900k |
| Hours of TTS | ~20hrs |
| Hours of STT | 50hrs |
| Studio Access | Yes |
| API Access | Yes |
| Max concurrency | 5 |
| Commercial use | Yes |
| Instant voice clone | 1000 |
| Pay as you go | $5.0 |
M
$340/month
| Credits | 9M |
| Hours of TTS | ~200hrs |
| Hours of STT | 500hrs |
| Studio Access | Yes |
| API Access | Yes |
| Max concurrency | 10 |
| Commercial use | Yes |
| Instant voice clone | 1000 |
| Pay as you go | $4.0 |
L
$1,615/month
| Credits | 45M |
| Hours of TTS | ~1000hrs |
| Hours of STT | 2500hrs |
| Studio Access | Yes |
| API Access | Yes |
| Max concurrency | 15 |
| Commercial use | Yes |
| Instant voice clone | 1000 |
| Pay as you go | $3.8 |