AI voice generators , by Smallest AI Inc. , since 2023
Smallest.ai
Pay-as-you-go voice-agent API billed per minute for TTS, calls and hosting
- API
- WEB
What Smallest.ai does
Smallest.ai is a developer-focused voice-agent and TTS/STT API platform with per-minute usage pricing (no seat-based subscription tiers), covering text-to-speech, speech-to-text, voice-agent hosting, phone numbers and knowledge-base add-ons for building conversational voice products.
What you get: Per-minute pay-as-you-go pricing (no subscription tiers), Real-time transcription with built-in PII redaction, Voice-agent hosting and phone number provisioning, Knowledge-base integration for agents, Multi-language accuracy for diverse teams, per G2 reviews.
Typical jobs: Building and hosting voice agents for call centers; Real-time transcription with compliance/PII redaction needs; High-volume API TTS/STT billed strictly by usage.
Worth knowing: Added as a replacement for Play.ht, which was excluded from this list: Play.ht's team was acquihired by Meta in July 2025 and the service was shut down (API went dark July 26, 2025; consumer site followed by early 2026), with all accounts, voice clones and saved audio permanently deleted and no migration/export path, confirmed by multiple independent sources (murf.ai's own PlayHT-migration blog post, toolsforhumans.ai, texttolab.com). Smallest.ai is a live, real, longtail voice-agent API pick with only one G2 complaint quote found (limited third-party review volume, consistent with a newer/niche product).
What users complain about: The advanced pronunciation dictionary manager in the developer portal feels a bit bare-bones; documentation could be improved for better onboarding and advanced configurations. (https://www.g2.com/products/smallest-ai/reviews)
Pricing and plan limits
Verified August 2026| Plan | Monthly | Annual (per mo) | Limits |
|---|---|---|---|
| Pay As You Go | not disclosed | n/a | $10 free starter credit; Text-to-Speech ~$0.09/min, Speech-to-Text ~$0.009/min, voice agent calls $0.09-$0.21/min, hosting $0.01/min flat, 20 concurrency included, phone numbers $10/number/month, knowledge base $3/GB/user |
| Enterprise | not disclosed | n/a | Custom pricing for infrastructure, models and add-ons; 99.99% uptime SLA |
Where it wins
- Granular per-minute/per-feature pricing means very small projects can start for a few dollars rather than committing to a subscription tier
- G2 reviewers consistently praise real-time transcription accuracy and built-in PII redaction for compliance-sensitive workflows
Where it falls short
- No ongoing free tier, only a one-time $10 starter credit, so sustained testing requires paying
- Documentation is thinner than incumbents: the pronunciation-dictionary manager is described as bare-bones and onboarding docs could be improved, per G2 reviews
How we scored it
Full methodology| Criterion | Weight | Score | Contribution |
|---|---|---|---|
| Capability | 30% | 7.5 | 2.25 |
| Value for money | 25% | 8.0 | 2.00 |
| Ease of use | 15% | 6.0 | 0.90 |
| Maturity | 15% | 5.5 | 0.82 |
| Support & docs | 10% | 5.5 | 0.55 |
| Momentum | 5% | 7.5 | 0.38 |
| Weighted total | 100% | 6.9 | 6.90 |
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