# Google Cloud Text-to-Speech vs Inworld Realtime TTS-2 (slim)

> Google Cloud Text-to-Speech scores 66.9 (B) to Inworld Realtime TTS-2's 58.3 (C) for text-to-speech. Prices, MCP, x402, uptime and agent notes side by side.

- Full: https://www.anchorterminal.com/compare/google-cloud-tts-vs-inworld-tts.md (~5,300 tokens) · this version ~3,130 tokens · JSON https://www.anchorterminal.com/compare/google-cloud-tts-vs-inworld-tts.json · canonical https://www.anchorterminal.com/compare/google-cloud-tts-vs-inworld-tts
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · MCP: https://www.anchorterminal.com/mcp · Updated: 2026-11-07
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Google Cloud Text-to-Speech scores 66.9 (B) on agent readiness against Inworld Realtime TTS-2's 58.3 (C), and leads in 4 of 7 scored categories. Inworld Realtime TTS-2 leads on payments & pricing and maintenance & community. Both do text-to-speech.

- Google Cloud Text-to-Speech: B 66.9, rank #351 of 1510 · https://www.anchorterminal.com/tools/google-cloud-tts.min.md
- Inworld Realtime TTS-2: C 58.3, rank #756 of 1510 · https://www.anchorterminal.com/tools/inworld-tts.min.md
- Google Cloud Text-to-Speech, good for Teams already on Google Cloud wanting many languages, SSML and an SLA. Ahead on Reliability, 85 against 62; Schema & documentation, 80 against 60; Security & auth, 80 against 61; Transparency & trust, 87 against 63.
- Inworld Realtime TTS-2, good for Agents that generate replies or stories at runtime and want delivery chosen from context without writing tags, and for per-message or pre-generated audio. Ahead on Payments & pricing, 40 against 20; Maintenance & community, 68 against 25. Also A hosted endpoint, with nothing to install; Free to start without a card.

| Category | Google Cloud Text-to-Speech | Inworld Realtime TTS-2 |
| --- | --- | --- |
| Reliability (16%) | 85 | 62 |
| Performance (10%) | pending | pending |
| Schema & documentation (13%) | 80 | 60 |
| Agent ergonomics (13%) | 65 | 68 |
| Security & auth (14%) | 80 | 61 |
| Payments & pricing (10%) | 20 | 40 |
| Task success (10%) | pending | pending |
| Maintenance & community (7%) | 25 | 68 |
| Transparency & trust (7%) | 87 | 63 |

| Fact (where they differ) | Google Cloud Text-to-Speech | Inworld Realtime TTS-2 |
| --- | --- | --- |
| Vendor | Google Cloud | Inworld AI |
| Hosted endpoint | no (local only) | `https://api.inworld.ai` |
| Transports | HTTP | HTTP, websocket |
| Auth | OAuth | API key |
| Pricing | Pay per use | Freemium |
| Price for text-to-speech | $10 per 1M tokens | $12.50 per 1M characters |
| Licence | none | Proprietary service under Inworld's Terms of Service. The Node.js SDK `@inworld/tts` and the CLI `@inworld/cli` are MIT on npm |
| Tools exposed | 0 | none |
| llms.txt | no | yes |
| Last release | 2025-12-30 | 2026-10-28 |
| Terms last updated | 2026-09-02 | 2025-06-11 |
| Privacy policy last updated | 2026-10-01 | 2026-01-18 |
| Customer content may train models | yes | not found in the text |
| Popularity | none | 3.6k npm/wk |

Why the edge:
- Maintenance & community, Inworld Realtime TTS-2 +43: Google Cloud Text-to-Speech 25 (Read as a model. The newest release note is still 30 December 2025 (Chirp 3 HD in yue-HK), 311 days ago, and `gemini-3.1-flash-tts-preview` appears on the Gemini-TTS page with no dated note (0). In the 90 days from 8 August the Python client shipped 2.38.0 on 1 October, whose only change declares Python 3.15 support, which counts half and can't set the recency line (0). Release notes, a public issue tracker and paid support (10 of 15). Official client libraries, Python at 2.38.0 and Node at 7.2.0 (10 of 15). Package CI not checked (5 of 10). Total 25.); Inworld Realtime TTS-2 68 (Read as a model. Reasoning and an updated `inworld-tts-2` on 28 October 2026, and `@inworld/cli` 1.5.0 on 29 October (30). Dated TTS changes on 6 August, 9 August, 11 September and 28 October 2026 (10). `inworld-tts-1` and `-1-max` were discontinued on 15 June 2026 with requests routed to newer models, and the 1.5 models are deprecated with no end date, but no notice period was found (5 of 10). Public release notes, a Discord server and support@inworld.ai, with no evidence read of how they answer (8 of 15). `@inworld/tts` 1.1.1 dates from 6 May 2026, before TTS-2 Flash and Reasoning, and the PyPI page answered with a bot check (10 of 15). The CLI is current, but the SDK and CLI repositories weren't read (5 of 10). Total 68.)
- Transparency & trust, Google Cloud Text-to-Speech +24: Google Cloud Text-to-Speech 87 (Closed service under the Google Cloud terms, with Apache-2.0 clients (15). The data logging page, the terms and the privacy notice agree that TTS text and audio aren't logged, and a DPA and sub-processor list exist, as read for google-speech-to-text (25 of 30). Release notes mark preview and GA, and the Cloud terms carry notice before a GA capability is discontinued, but Gemini-TTS is moving to the Agent Platform API with no dated notice for the Cloud TTS models (15 of 20). Regional endpoints (global, us, eu and others) and a public sub-processor list (20). Total 75.); Inworld Realtime TTS-2 63 (Closed service with clear terms naming Theai, Inc. dba Inworld AI, and MIT client packages on npm (15). The zero data retention page is specific about what is kept, but the Terms' no-training clause and the Privacy Notice's training use sit side by side without a reconciling sentence, and the privacy retention section gives no periods apart from up to three years for voice-derived biometric data (14 of 30). Dated discontinuation of `inworld-tts-1` with automatic rerouting and release-stage definitions, but no written notice policy, and the 28 October update replaced `inworld-tts-2` in place (12 of 20). US headquarters with isolated EU and India regions on Enterprise. No sub-processor list was found in the docs, and the trust centre wasn't read (10 of 20). Total 51.)
- Reliability, Google Cloud Text-to-Speech +23: Google Cloud Text-to-Speech 85 (Google Cloud status page with a per-product history (20). None of the four Google Cloud incidents since 8 August (20 August, 1 September, 8 and 9 October, and the europe-west2 incident of 20 October, which listed Speech-to-Text among 38 products) names Text-to-Speech. The public page shows only broad incidents, so clean is read with that limit (30). Quotas published with numbers, 1,000 requests a minute for most voices, 200 for Chirp 3, 500 for Studio, 100 concurrent streams and 100 long-audio requests a minute (15). The quotas page (last updated 26 October 2026) says nothing about the error a breach returns or how to back off, read as google-speech-to-text was (0). A 99.9 per cent monthly SLA with credits of 10, 25 and 50 per cent, read on 6 November (10). Chirp 3 HD and Gemini 2.5 Flash and Pro TTS are GA, with Gemini 3.1 Flash TTS and Flash-Lite in preview (10). 20 + 30 + 15 + 0 + 10 + 10 = 85.); Inworld Realtime TTS-2 62 (Hosted reading of the checklist, on the TTS API. status.inworld.ai is a public status page running the issue-status app, which draws components and incidents from GitHub issues (20). The page is still a script shell on 4 November, and its history wasn't read, because GitHub's pages answer our proxy with 403, so no readable history (5). Concurrent generations, WebSocket connections and cloning and design requests a minute are published per plan, from 5 concurrent generations on the free plan to 500 on Growth (15). A 429 is documented with exponential backoff and jitter code, and the concurrency error (code 8) says which messages may have been dropped, but no Retry-After header is documented (12 of 15). An SLA is named on the Enterprise plan only, with no terms or uptime figure published (0). TTS-2 reached general availability on 31 August 2026 and Reasoning carries no Preview mark. Async and batch jobs are Preview (10). Total 62.)
- Schema & documentation, Google Cloud Text-to-Speech +20: Google Cloud Text-to-Speech 80 (Discovery document revision 20260827 with typed methods and 26 schemas, and protocol buffers for gRPC (25). No llms.txt found (0). The Chirp 3 HD and Gemini-TTS pages say which voices suit which use and list formats and limits, but the reference doesn't say when to choose streaming or long audio (15 of 20). Typed messages with enums for encoding and gender and required fields (15). Samples in several languages, standard status codes with little method-specific error detail (10 of 15). Versioned v1 and v1beta1 with dated release notes (15). Total 80.); Inworld Realtime TTS-2 60 (No OpenAPI or other machine-readable file was found. llms.txt and the API reference don't link one and the usual paths redirect to pages (0). llms.txt, llms-full.txt, a Markdown twin of every page and a keyless docs MCP server (10). The models page says which model suits what, the Reasoning guide says where it runs and where it doesn't yet (WebSocket, Realtime, batch), and the reference marks fields each model ignores (17 of 20). Typed fields with enums for encoding, `deliveryMode`, `reasoning` and `timestampType`, a sample-rate range, per-endpoint text limits and a 600-character cap on `reasoningContext` (14 of 15). Examples in curl, Python, JavaScript and the CLI, with one 4XX example and the concurrency error, and no TTS error list (9 of 15). Versioned `/v1` paths and dated TTS release notes, but the notes have no entry for the 28 October Reasoning launch and model update, and models have no dated snapshots (10 of 15). Total 60.)
- Payments & pricing, Inworld Realtime TTS-2 +20: Google Cloud Text-to-Speech 20 (No x402, MPP or L402 (0). Per-character and per-token prices for every voice family published without a login (20). Monthly free characters (1 million for Chirp 3 HD, 4 million for Standard and WaveNet) need billing enabled, which needs a card (0). A person creates a project and billing account in a browser (0). Total 20.); Inworld Realtime TTS-2 40 (No x402, MPP or L402 (0). Per-character prices for both models and every plan are on the public pricing page, $25 per million characters for TTS-2 on the free plan (20). The On-Demand plan is free with up to 70 minutes of TTS, and the pricing table lists no payment method for it (20). `inworld login` opens a browser sign-in and the CLI mints keys only after it, so a person signs up (0). Total 40.)
- Security & auth, Google Cloud Text-to-Speech +19: Google Cloud Text-to-Speech 80 (Model reading of the checklist, with training and retention in place of the least-privilege and injection lines. OAuth 2.0 with service accounts and IAM roles per project (30). The discovery document lists `access_token`, `oauth_token` and `key` as query parameters, so 10 off, as every Google API listing in this run (20 of 30). The data logging page says Google doesn't log any customer Cloud TTS text or audio (20). The service is stateless and keeps no content (15). Because it is stateless, Data Access audit logs don't apply, leaving admin activity only (5 of 15). Valid security.txt, Google's vulnerability reward programme, SOC 2 and ISO 27001 and public Cloud security bulletins, as on google-speech-to-text (20). Total 80.); Inworld Realtime TTS-2 61 (Model reading of the checklist, with training and retention in place of the least-privilege and injection lines. Workspace API keys, deleted to revoke, with separate keys per environment advised, single-use client tokens valid 15 minutes, and a Realtime-only key type. No key can be limited to TTS, because write toggles cover only the Voice and Router APIs (25 of 30). The Terms (11 June 2025) say Inworld won't train generally available models on customers' non-public Materials, except feedback and content flagged for trust and safety. The Privacy Notice (18 January 2026) lists training AI models among its uses and covers voice data, while excluding data processed for enterprise customers (12 of 20). Zero data retention is Enterprise only or a Growth add-on. No retention period is published for other plans, async results are kept about 7 days, and whether the Reasoning model's step is covered isn't stated (6 of 15). Usage is attributed per key, and a Performance page (Builder and above) shows errors, latency and throttling. The Logs page sits behind the Portal login and wasn't read (8 of 15). SOC 2 Type II, HIPAA and GDPR claimed on the security page, with the trust centre unread. A vulnerability report form exists. No security.txt (404) and no bug bounty found (10 of 20). Total 61.)

| Task | Google Cloud Text-to-Speech | Inworld Realtime TTS-2 |
| --- | --- | --- |
| Narrate a 9,000-character script | $0.04 to $1.44 | $0.11 to $0.22 |