# Google Gemini Live API vs OpenAI Realtime API

> Google Gemini Live API vs OpenAI Realtime API: OpenAI Realtime API is our pick, leading for developers and ecommerce. They split on native integrations count.

Google Gemini Live API (Native-audio speech-to-speech model API (Gemini Live) with barge-in, affective dialog, and tool use over a stateful WebSocket.) and OpenAI Realtime API (Frontier speech-to-speech model API (gpt-realtime family) for low-latency voice agents over WebRTC, WebSocket, and SIP.) are Voice AI platforms. Below: the bottom line, verified head-to-head facts, and real production costs.

Voice AI platforms · 13 facts compared · all sourced · pricing verified Jul 30, 2026

## Bottom line

OpenAI Realtime API claims three outright wins across custom pipeline control, ecommerce support, and outbound sales campaigns, while Google Gemini Live API wins none. A decisive structural advantage is native SIP trunking support, which Google Gemini Live API lacks entirely. SIP trunking lets teams connect existing telephony infrastructure directly, making outbound sales campaigns and ecommerce support deployments far simpler to build and operate. On custom pipeline control, OpenAI Realtime API's native WebRTC, WebSocket, and SIP integration paths alongside MCP and tool calling give developers precise control over call flow that LiveKit or Pipecat middleware layers cannot fully replicate. Google Gemini Live API's $0.018/min base rate and 70-language support are genuine strengths, but they did not translate into a single outright win.

## Verdict summary

| Use case | Winner | Why |
| --- | --- | --- |
| No-code agency deploys | Tie | For a no-code agency deploying and white-labeling voice AI, the deciding factors are a no-code agent builder and white-label sub-account support. |
| Custom pipeline control | OpenAI Realtime API | Both tools are API-first and neither supports bring-your-own LLM, so those critical pipeline-control factors cancel out. |
| Ecommerce support and orders | OpenAI Realtime API | For ecommerce support flows, integration breadth is the deciding factor. |
| Healthcare compliance | Tie | For HIPAA-bound healthcare workflows, the single most critical requirement is a signed HIPAA Business Associate Agreement, followed closely by SOC 2 Type II certification and consent/recording compliance tooling. |
| Outbound sales campaigns | OpenAI Realtime API | For outbound sales campaigns, connecting to existing phone infrastructure is a critical practical requirement. |
| SMB receptionist and booking | Tie | For an SMB receptionist and booking scenario, the deciding factors are platform fee, built-in knowledge base, no-code agent builder, warm transfer, and number provisioning. |

## Google Gemini Live API vs OpenAI Realtime API: head-to-head facts

| Fact | Google Gemini Live API | OpenAI Realtime API | Verified |
| --- | --- | --- | --- |
| Base price / min | $0.02 ([source](https://ai.google.dev/gemini-api/docs/pricing)) | n/a | Jul 30 |
| Native SIP trunking | ✗  No ([source](https://ai.google.dev/gemini-api/docs/live)) | ✓  Yes ([source](https://developers.openai.com/api/docs/guides/realtime-sip)) | Jul 30 |
| Bring-your-own LLM | ✗  No ([source](https://ai.google.dev/gemini-api/docs/live)) | ✗  No ([source](https://developers.openai.com/api/docs/guides/realtime)) | Jul 30 |
| Free tier credit | Free tier (rate-limited) ([source](https://ai.google.dev/gemini-api/docs/pricing)) | n/a | Jul 30 |

## Google Gemini Live API vs OpenAI Realtime API pricing: true cost at 3 usage tiers

All-in monthly: platform fee + per-minute + telephony. Assumes GPT-4o class model, ElevenLabs voice.

| Volume | Buyer | Google Gemini Live API | OpenAI Realtime API | Note |
| --- | --- | --- | --- | --- |
| 1K min/mo | Solo builder | $18 | n/a | Includes estimated telephony. Free credits can offset the first month. |
| 10K min/mo | Agency | $180 | n/a | Volume pricing typically starts to apply at this tier. |
| 100K min/mo | Call center | $1,800 | n/a | Both platforms offer custom contracts at this tier. Negotiate. |

## Google Gemini Live API vs OpenAI Realtime API: verdicts by use case

### No-code agency deploys → Tie

For a no-code agency deploying and white-labeling voice AI, the deciding factors are a no-code agent builder and white-label sub-account support. Neither OpenAI Realtime API nor Google Gemini Live API has verified coverage of either attribute. Both are developer-first APIs requiring code, and neither offers white-label or reseller account structures. On cost, Gemini Live API runs $0.018 per minute with a free tier, while OpenAI Realtime API pricing is not stated. With the two most critical buying criteria unanswered for both tools, no winner can be named.

### Custom pipeline control → OpenAI Realtime API

Both tools are API-first and neither supports bring-your-own LLM, so those critical pipeline-control factors cancel out. The tiebreaker for engineering teams building custom pipelines is native SIP trunking: OpenAI Realtime API supports it natively, while Google Gemini Live API does not. SIP connectivity is essential for teams wiring real telephony into a custom pipeline without adding a separate third-party layer. OpenAI also exposes WebRTC, WebSocket, and SIP transport plus MCP and tool calling, giving engineering teams more low-level control over the call path.

### Ecommerce support and orders → OpenAI Realtime API

For ecommerce support flows, integration breadth is the deciding factor. OpenAI Realtime API connects via WebRTC, WebSocket, and SIP plus MCP and tool calling, giving developers direct hooks into order management systems, payment processors, and CRMs. Google Gemini Live API lists LiveKit, Pipecat, Voximplant, and Agora, which are media-layer partners rather than business-app connectors. Both tools offer self-serve signup and no annual contract. Neither publishes a built-in knowledge base or platform fee facts. OpenAI Realtime API also supports native SIP trunking, which aids ecommerce telephony deployments, while Gemini Live API has none.

### Healthcare compliance → Tie

For HIPAA-bound healthcare workflows, the single most critical requirement is a signed HIPAA Business Associate Agreement, followed closely by SOC 2 Type II certification and consent/recording compliance tooling. Verified data on HIPAA BAA availability, SOC 2 Type II status, consent/recording compliance tooling, GDPR controls, and warm transfer capabilities is unavailable for either OpenAI Realtime API or Google Gemini Live API. Without evidence on these decisive attributes, neither tool can be shown to lead on what matters most for healthcare compliance. Attributes that are documented, such as native SIP trunking (yes for OpenAI Realtime API, no for Google Gemini Live API) and base pricing ($0.018/min for Google Gemini Live API), are secondary concerns here and cannot override the missing compliance evidence.

### Outbound sales campaigns → OpenAI Realtime API

For outbound sales campaigns, connecting to existing phone infrastructure is a critical practical requirement. OpenAI Realtime API supports native SIP trunking while Google Gemini Live API does not, meaning teams can route calls through standard carriers and PBX systems directly with OpenAI Realtime API, without additional middleware layers. On pricing, Google Gemini Live API is listed at $0.018/min, while OpenAI Realtime API pricing is not directly comparable from available information, so no cost advantage can be confirmed for either side. Both platforms are API-first with self-serve signup and no annual contract required. Native SIP trunking support is the deciding factor for outbound call-center campaigns, where dialing out through telecom infrastructure is fundamental to operations.

### SMB receptionist and booking → Tie

For an SMB receptionist and booking scenario, the deciding factors are platform fee, built-in knowledge base, no-code agent builder, warm transfer, and number provisioning. Neither tool publishes information covering monthly platform fee, built-in knowledge base, no-code agent builder, or warm transfer capability, so those critical attributes cannot be scored for either side. On number provisioning, OpenAI Realtime API does not support buying or porting numbers in-platform, and no confirmation exists that Google Gemini Live API does either. With the most important attributes unresolvable, neither tool can be declared the winner.

## Google Gemini Live API vs OpenAI Realtime API: common questions

### Is OpenAI Realtime API cheaper than Google Gemini Live API?

Pricing depends on usage type. Google Gemini Live API charges $0.018 per minute. OpenAI Realtime API pricing varies by model and input/output tokens rather than a simple per-minute rate, so a direct per-minute comparison is not straightforward. Neither requires an annual contract for best pricing. Check each provider's current pricing page for your specific use case to determine which is cheaper.

### OpenAI Realtime API vs Google Gemini Live API: which is better for no-code agency deploys?

Neither platform is ideal for no-code agency deployments out of the box. Both are API-first tools aimed at developers, with no native no-code workflow builder, no built-in number provisioning, and no direct integrations with common agency tools like GoHighLevel, HubSpot, or Zapier. OpenAI Realtime API supports native SIP trunking, which can simplify telephony setup, while Google Gemini Live API does not. Agencies without dev resources will likely need a third-party platform on top of either.

### Does OpenAI Realtime API or Google Gemini Live API support native SIP trunking for telephony integration?

OpenAI Realtime API includes native SIP trunking support, making it straightforward to connect directly to telephony infrastructure. Google Gemini Live API does not offer native SIP trunking, so you would need a third-party bridge such as Voximplant or Twilio to handle phone calls.

### Can I try Google Gemini Live API without paying upfront?

Yes. Google Gemini Live API offers a free tier with rate-limited access, letting you prototype and test before committing to paid usage. No annual contract is required for the best pricing either, so you can scale on a pay-as-you-go basis.

### Do OpenAI Realtime API or Google Gemini Live API require an annual contract to get their standard rates?

Neither tool requires an annual contract for its standard pricing. Both OpenAI Realtime API and Google Gemini Live API offer their rates without locking you into a long-term commitment, which is useful for teams that need flexibility during early deployment.

### What does Google Gemini Live API cost per minute?

Google Gemini Live API is priced at $0.018 per minute. This charge is billed as you use the service, with no annual contract required to access this rate.

### Do OpenAI Realtime API or Google Gemini Live API support barge-in so callers can interrupt the bot mid-speech?

Both OpenAI Realtime API and Google Gemini Live API support interruption handling (barge-in), allowing a caller to speak over the bot while the system responds naturally. This capability is important for conversational voice agents, where rigid turn-taking feels unnatural.

### Can I bring my own TTS voice or my own LLM to either OpenAI Realtime API or Google Gemini Live API?

Neither tool currently supports bringing your own LLM, and OpenAI Realtime API does not support bringing your own TTS voice. Both platforms are closed ecosystems in this respect, so if custom voice or model flexibility is a priority, other solutions may be worth evaluating.

### Which integration ecosystems do OpenAI Realtime API and Google Gemini Live API connect to out of the box?

OpenAI Realtime API integrates via WebRTC, WebSocket, and SIP, and supports MCP plus tool calling. Google Gemini Live API connects natively with LiveKit, Pipecat, Voximplant, and Agora, among others. Your existing stack should guide which fits more cleanly into your architecture.

Source: https://www.versusref.com/voice-ai/gemini-live-api-vs-openai-realtime-api/