Compare

Inworld TTS 2 vs TTS 1.5 Mini

Pricing per million tokens, context window, capabilities — pulled from each provider's public docs. All 2 are available via the same AIgateway OpenAI-compatible endpoint; flip the model string to switch.

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Inworld TTS 2
inworld/tts-2
T1
TTS 1.5 Mini
inworld/tts-1.5-mini
Provider
Inworld
Inworld
Family
Inworld TTS
Inworld TTS
Modality
audio-tts
audio-tts
Context window
Max output
Released
2026-05-05
2026-04-13
License
Proprietary
Proprietary
Per 1K chars
$0.035 /1K ch
$0.025 /1K ch
Tools
Streaming
Vision
JSON mode
Reasoning
Prompt caching
Batch API
Try it
Open in playground →
Open in playground →
Inworld TTS 2
inworld/tts-2
Full spec →

Inworld's most powerful and expressive text-to-speech model. Builds on TTS 1.5 with rich expressive speech, real-time latency, natural language steering (e.g. [whisper], [say excitedly]), and stronger multilingual support across 15 production languages plus 90+ experimental languages.

Strengths
  • Natural speech synthesis
Use cases
VoiceoversIVRAudiobooks
TTS 1.5 Mini
inworld/tts-1.5-mini
Full spec →

Ultra-fast, cost-efficient text-to-speech with approximately 120ms latency and 15-language support.

Strengths
  • Natural speech synthesis
Use cases
VoiceoversIVRAudiobooks

Compare with another

GPT-5.5 Pro vs Inworld TTS 2
openai/gpt-5.5-pro · inworld/tts-2
GPT-5.5 vs Inworld TTS 2
openai/gpt-5.5 · inworld/tts-2
Claude Opus 4.7 vs Inworld TTS 2
anthropic/claude-opus-4.7 · inworld/tts-2
Claude Sonnet 4.6 vs Inworld TTS 2
anthropic/claude-sonnet-4.6 · inworld/tts-2
Kimi-K2.6 vs Inworld TTS 2
moonshot/kimi-k2.6 · inworld/tts-2
Gemini 3.1 Pro vs Inworld TTS 2
google/gemini-3.1-pro · inworld/tts-2
Gemini 3 Flash vs Inworld TTS 2
google/gemini-3-flash · inworld/tts-2
Grok 4 vs Inworld TTS 2
xai/grok-4 · inworld/tts-2
HappyHorse 1.0 T2V vs Inworld TTS 2
alibaba/hh1-t2v · inworld/tts-2
SWITCH BETWEEN THEM

One key, all 2, one line different.

from openai import OpenAI

client = OpenAI(
    base_url="https://api.aigateway.sh/v1",
    api_key="sk-aig-...",
)

# Inworld TTS 2
client.chat.completions.create(
    model="inworld/tts-2",
    messages=[{"role":"user","content":"hello"}],
)

# TTS 1.5 Mini
client.chat.completions.create(
    model="inworld/tts-1.5-mini",
    messages=[{"role":"user","content":"hello"}],
)
Get an AIgateway keyRun an eval on these →