What should I use for speech synthesis in a production app?

For a production app, the best choice depends on your priorities, but in general:

Best default choice

Use a cloud TTS service if you need:

• high-quality voices
• reliability at scale
• easy setup
• multilingual support
• consistent latency

Common production-grade options:

• Amazon Polly
• Google Cloud Text-to-Speech
• Azure Speech
• OpenAI TTS if you want very natural-sounding voices and simple integration

When to use each

1. Cloud TTS services

Best for most production apps.

Pros

• Strong voice quality
• Easy to integrate
• Scales well
• No need to manage models/infra
• Usually supports SSML and multiple voices

Cons

• Ongoing cost
• Requires network access
• Vendor lock-in
• Latency depends on network and service

2. On-device / browser TTS

Good if you need:

• offline support
• low cost
• privacy
• instant local playback

Examples:

• Browser SpeechSynthesis API
• iOS/macOS AVSpeechSynthesizer
• Android TextToSpeech

Pros

• No API cost
• Works offline on device
• Simple if you’re already building native apps

Cons

• Voice quality varies a lot
• Platform differences
• Less control and consistency
• Browser support can be inconsistent

3. Self-hosted/open-source TTS

Best if you need:

• full control
• data privacy
• custom voices
• predictable costs at scale

Examples:

• Piper
• Coqui TTS
• eSpeak NG for lightweight/robotic speech

Pros

• Data stays in your environment
• Can be cheaper at high volume
• Customizable

Cons

• You operate the infrastructure
• More engineering effort
• Quality and scaling can be harder

Practical recommendation

If you’re building a serious production app and want the safest default:

• Use a cloud TTS provider
• Prefer OpenAI TTS or Google/Azure/Amazon depending on:
  • voice quality
  • pricing
  • required regions/compliance
  • latency
  • existing cloud stack

Selection checklist

Choose based on:

• Voice quality
• Latency
• Cost per character/minute
• Languages
• SSML support
• Streaming support
• Compliance/privacy needs
• Ability to cache generated audio

Important production tip

Whatever you choose:

• cache synthesized audio
• pre-generate common prompts
• set fallbacks
• measure latency and cost
• avoid synthesizing the same text repeatedly

If you want, I can give you a ranked recommendation by use case like:

• mobile app
• web app
• IVR/call center
• accessibility reader
• game/NPC voices
• offline/local-first app