Inworld AI vs Convai
Both build conversational AI NPCs with memory, emotion, and Unity/Unreal integration, so the choice comes down to billing model and platform shape. Inworld runs on subscription credits (On-Demand free tier for prototyping, paid from Creator $25/mo) and bundles a full voice stack — TTS, STT, speech-to-speech — plus an LLM router with 220+ models in one platform. Convai is interaction-metered (free 100 interactions/month, Indie Dev from $22/mo on yearly billing for 3,000 interactions) and emphasizes multimodal perception: characters that see, hear, and act in the scene, with knowledge banks for grounding dialogue. There is no measured quality winner in this review.
| Decision point | Inworld AI | Convai |
|---|---|---|
| Best suited to | Developers building voice agents and real-time conversational apps that need low-latency speech APIs. | Game, XR and web developers building conversational AI avatars, AI NPCs and virtual humans that can see, hear and speak inside an experience. |
| Plans and cost | On-Demand $0 pay-as-you-go (TTS-2 $25 per 1M characters, TTS-2 Flash $15 per 1M, STT $0.15 per hour; includes up to 70 TTS minutes, 100 custom voices, 2 professional clones, and a commercial license). Creator $25/month ($25 credit; TTS-2 $20 per 1M, Flash $10, STT $0.10 per hour). Builder $100/month ($17.50/$9/$0.10; 3,000 voices). Developer $300/month ($15/$8/$0.10; 10,000 voices). Growth $1,500/month ($12.50/$7/$0.10; 30,000 voices; ZDR, HIPAA, and BAA as add-ons). Enterprise custom (TTS-2 as low as $5 per 1M). Credits equal the tier price and roll over up to 3 months; LLM inference starts at $0.07 per 1M tokens; 200+ languages; all tiers include GDPR and SOC 2 Type II. | Free is $0/mo with a 100/month Interaction Quota and 60 mins of Cloud Rendered Avatar Studio and Convai Sim. Indie Dev is $29/mo billed monthly or $22/mo billed yearly with a 3000/month Interaction Quota. Professional is $99/mo billed monthly or $69/mo billed yearly with a 10,000/month Interaction Quota. Scale is $499/mo billed monthly or $299/mo billed yearly with a 50,000/month Interaction Quota. Business is $1199/mo billed monthly or $499/mo billed yearly with a 125,000/month Interaction Quota. Enterprise is custom-priced with SLAs, data ownership terms and an on-prem deployment option. |
| Limitations | Inworld is no longer a character-design tool: the current product is a set of realtime voice APIs, so buyers looking for the old character creator will not find it here. Usage is metered by credits and characters, and HIPAA, ZDR, and BAA controls are add-ons rather than included on every tier. | The Free plan excludes the Knowledge Bank, long-term memory and character versioning, caps flagship LLM use at 50 interactions/month and allows only 1 monthly active end user and 1 character session concurrency. Experience embedding needs Professional or higher, and custom branding is only available with a yearly subscription on the top tiers. |
Use the same input
Build the same tavern-keeper NPC on both platforms — backstory, voice, and a memory of the player's name — deploy it into a Unity scene, and hold a 5-minute voice conversation that tests whether the NPC recalls an earlier fact.
What a successful result must preserve
The NPC must converse by voice in real time, remember a fact stated earlier in the session, run inside Unity or Unreal, and stay within a published free or entry-level paid tier.
Evidence and test status
Pricing and feature comparison based on publicly available information. Plan prices, interaction limits, and credit rates re-checked October 2026 against vendor pricing pages and October 2026 reviews. We did not run a hands-on NPC build or a scored conversation test; no quality ranking is claimed.
- Inworld AI — Inworld official pricing page ↗ (reviewed 2026-10-31), Inworld official homepage ↗ (reviewed 2026-10-31)
- Convai — Convai - Conversational AI for Virtual Worlds ↗