One Unified AI API.
Every Model You Need.
Stop juggling dozens of API keys and billing accounts. Access image, video, music, speech, and chat models — all through a single endpoint, a single key, a single balance.
Powering 50+ AI models from leading providers
The Models You Need. All in One Place.
From state-of-the-art image generators to cutting-edge LLMs — integrated and ready to use.
Suno
Suno AIFull-featured AI music generation platform. Supports text-to-music, extend tracks, upload audio covers, generate cover images, and timestamped lyrics. 7 API endpoints.
Kling 3.0
KuaishouState-of-the-art AI video generation with 4K quality support. Text-to-video and image-to-video capabilities.
Flux 2
Black Forest LabsHigh-quality AI image generation with excellent prompt following and photorealistic output.
ElevenLabs V3
ElevenLabsUltra-realistic text-to-speech with natural sounding voices. Supports multiple languages and voice styles.
Gemini
GoogleGoogle's most capable AI model for text generation, reasoning, and conversation.
Background Remover
API in OneRemove image backgrounds instantly with AI precision. Perfect for product photos, portraits, and e-commerce.
Multi-Modal, One Platform.
Photorealistic images from text prompts. Flux 2, Kling Image, and more.
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Cinematic AI video from text or images. Kling, Seedance, and more.
Original songs with Suno, natural voices with ElevenLabs. Audio, handled.
Access Gemini and other LLMs through an OpenAI-compatible format.
Built for Developers Who Ship.
Unified Billing
One credit balance. One invoice. No juggling subscriptions across a dozen AI platforms.
Enterprise Reliability
Redundant infrastructure with intelligent routing. Your app stays online, always.
Switch in Seconds
Change a model name in your request body. No SDK updates, no migration, no downtime.
Save More. Pay Only for What You Use.
No monthly subscriptions. No commitments. Just credits that work across every model.
| Model | Category | Official Price | API in One | You Save |
|---|---|---|---|---|
| Flux 2 | Image | $0.04/image | 10 credits (~$0.02) | 50% |
| Kling | Video | $0.32/video | 50 credits (~$0.10) | 69% |
| Suno | Music | $0.10/song | 20 credits (~$0.04) | 60% |
| ElevenLabs | Speech | $0.03/req | 5 credits (~$0.01) | 67% |
| Gemini | Chat | $0.01/req | 2 credits (~$0.004) | 60% |
| Face Swap | Tool | $0.05/req | 3 credits (~$0.006) | 88% |
Pay-as-You-Go
Buy credits when you need them. No recurring charges, no surprise invoices. Scale up or down instantly.
Transparent Pricing
Every API call shows exact credit cost upfront. Check your balance and usage history in real time.
Free Credits to Start
New accounts receive bonus credits — enough to test every model on the platform before committing.
Frequently Asked Questions
What is API in One?
API in One is a unified AI API gateway that aggregates 50+ AI models — including Flux 2, Kling, Suno, ElevenLabs, and Gemini — behind a single REST API. One API key, one credit balance, one consistent response format for image generation, video generation, music creation, text-to-speech, and chat.
How does billing work?
Pay-as-you-go with credits. Each model call costs a defined number of credits. No monthly subscriptions, no hidden fees. Buy credits when you need them.
Which models are supported?
Image generation (Flux 2, Kling Image, Ideogram), video generation (Kling 3.0, Seedance, Sora, Vidu, Runway), music generation (Suno), text-to-speech (ElevenLabs), chat and reasoning (Gemini, Kimi), and AI tools (Face Swap, Background Removal). We continuously integrate the latest AI models as they launch.
Do I need a separate key for each model?
No. That's the entire point. One API key works across all models. Specify the model name in your JSON body — done.
Is there a free tier?
Yes. New accounts get free bonus credits to explore any model on the platform. No credit card required to start.
What's the response format?
All responses use a consistent JSON structure: task ID, status, output data, and credit consumption. Async tasks (video, music) use polling via GET /api/v1/tasks/.
Are there rate limits?
Generous defaults designed for production workloads. Enterprise plans get higher limits. Requests are never throttled unexpectedly.
Can I use it commercially?
Absolutely. All generated content is cleared for commercial use, subject to individual model provider terms.
What if a model goes down?
Failed requests consume zero credits. The API returns clear error codes. We monitor all upstream providers and provide status transparency.
How fast is the API?
Our unified AI API gateway adds minimal latency (<50ms overhead). Actual generation time depends on the model — image generation via Flux 2 or Kling is typically 3–10 seconds, video generation 30–120 seconds, and chat responses are near-instant. Performance is comparable to calling providers directly.
Are there official SDKs or client libraries?
The API follows standard REST conventions, so any HTTP client works. For chat models, we're fully OpenAI-compatible — you can use the official OpenAI SDK, LangChain, or any OpenAI-compatible library by simply changing the base URL to apiin.one.
Do you support webhooks for async tasks?
Yes. For long-running tasks like video and music generation, you can optionally provide a callback URL. We'll POST the result to your endpoint when the task completes, so you don't need to poll.
How is my data handled?
We don't store your prompts, generated outputs, or API request content beyond the time needed to process the request. Generated assets are available for download for a limited period, then automatically purged. We never use your data for training.
Can I switch models without changing code?
Yes. All models within the same category share the same endpoint and request format. Switching from Flux 2 to Kling Image for image generation is as simple as changing the model parameter in your JSON body.
Do you offer team or organization accounts?
Yes. You can invite team members to share a credit balance and manage API keys under one organization. Usage analytics are available per-key, so you can track consumption across projects.
What's your uptime guarantee?
We target 99.9% uptime for the API gateway. Upstream model availability depends on individual providers, but we actively monitor all integrations and route around issues when possible.
Loved by Developers Worldwide
Join thousands of developers building with API in One.
"Switched from managing 6 different API keys to just one. API in One saved our team at least 10 hours a month on billing and key management alone."
"The unified billing is a game-changer. No more juggling credit cards across OpenAI, Stability, and ElevenLabs. One invoice, one balance."
"We swapped from Flux to Kling for image gen by changing one string in our request body. Zero downtime, zero code changes. Incredible."
"As a solo developer, I was spending more time on API integrations than on my actual product. API in One let me focus on what matters."
"Switched from managing 6 different API keys to just one. API in One saved our team at least 10 hours a month on billing and key management alone."
"The unified billing is a game-changer. No more juggling credit cards across OpenAI, Stability, and ElevenLabs. One invoice, one balance."
"We swapped from Flux to Kling for image gen by changing one string in our request body. Zero downtime, zero code changes. Incredible."
"As a solo developer, I was spending more time on API integrations than on my actual product. API in One let me focus on what matters."
"The response format is consistent across all models. Image, video, music — same JSON structure. My error handling code dropped by 60%."
"We use the video generation API for our marketing tool. Kling through API in One has been rock solid. 99.9% uptime is not just marketing talk."
"The free credits on signup let me prototype my entire AI art app before spending a single dollar. That kind of developer trust is rare."
"Latency is impressively low. The gateway adds almost nothing on top of the model providers own response time. Our users cant tell the difference."
"The response format is consistent across all models. Image, video, music — same JSON structure. My error handling code dropped by 60%."
"We use the video generation API for our marketing tool. Kling through API in One has been rock solid. 99.9% uptime is not just marketing talk."
"The free credits on signup let me prototype my entire AI art app before spending a single dollar. That kind of developer trust is rare."
"Latency is impressively low. The gateway adds almost nothing on top of the model providers own response time. Our users cant tell the difference."
"Music generation through Suno via API in One is seamless. We built a custom jingle generator for our clients in under a week."
"I compared costs: subscribing to 5 AI platforms individually vs. API in One credits. Saved roughly 40% on our monthly AI spend."
"The documentation is clean and the curl examples work out of the box. I had my first image generated within 3 minutes of signing up."
"We run a SaaS with 10K+ users hitting AI models daily. The intelligent routing means our app stays responsive even during provider outages."
"Music generation through Suno via API in One is seamless. We built a custom jingle generator for our clients in under a week."
"I compared costs: subscribing to 5 AI platforms individually vs. API in One credits. Saved roughly 40% on our monthly AI spend."
"The documentation is clean and the curl examples work out of the box. I had my first image generated within 3 minutes of signing up."
"We run a SaaS with 10K+ users hitting AI models daily. The intelligent routing means our app stays responsive even during provider outages."
"OpenAI-compatible format was the selling point for us. We migrated our existing ChatGPT integration to also use Gemini without touching a single endpoint."
"Text-to-speech quality through ElevenLabs API is identical to calling them directly. No quality loss, but way simpler auth and billing."
"The task polling system for async jobs (video, music) is elegant. One GET endpoint, works the same regardless of which model generated the content."
"Enterprise reliability that feels indie-developer friendly. Best of both worlds. Our CTO approved it in one meeting after seeing the docs."
"OpenAI-compatible format was the selling point for us. We migrated our existing ChatGPT integration to also use Gemini without touching a single endpoint."
"Text-to-speech quality through ElevenLabs API is identical to calling them directly. No quality loss, but way simpler auth and billing."
"The task polling system for async jobs (video, music) is elegant. One GET endpoint, works the same regardless of which model generated the content."
"Enterprise reliability that feels indie-developer friendly. Best of both worlds. Our CTO approved it in one meeting after seeing the docs."
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