Cloud API providers for accessing AI models without local hardware.
API providers offer cloud-hosted AI models accessible via HTTP APIs β no hardware, no model management, pay-per-use pricing. The big three (OpenAI, Anthropic, Google) develop their own frontier models, while inference providers (Together AI, Groq, Fireworks) host open-source models at competitive prices. Aggregators like OpenRouter provide a single API for all providers.
Choosing a provider involves balancing model quality, latency, cost, and features. OpenAI offers the broadest ecosystem, Anthropic excels at complex reasoning and safety, Google provides the largest context windows. For open models, inference providers can be 5-10x cheaper than the big three. Understanding the landscape helps you optimize for your specific use case.
OpenAI API
GPT-4o, GPT-4-turbo, o1/o3 reasoning models. The largest ecosystem: assistants, fine-tuning, image generation (DALL-E), speech-to-text (Whisper), embeddings. The default choice for most projects.
Anthropic API
Claude Opus, Sonnet, and Haiku models. Excels at complex analysis, coding, and long-context tasks (200K tokens). Features: tool use, vision, prompt caching, batch API. Known for safety and instruction-following.
Google AI (Gemini)
Gemini Pro and Ultra with 1M+ token context windows. Gemini API for developers, Vertex AI for enterprise. Multimodal native: text, images, video, audio in one model. Competitive pricing.
OpenRouter
Unified API gateway for 100+ models across all major providers. Single API key, consistent format, automatic fallbacks. Great for comparing models or switching providers without code changes.
Together AI
Leading open-source model hosting. Runs Llama, Mixtral, Qwen, and other open models at low cost. Fine-tuning service included. Often 5-10x cheaper than frontier model APIs for similar-quality open models.
Groq
Specialized inference provider using custom LPU chips. Extremely fast inference (500+ tokens/second) for supported models. Best for latency-critical applications where speed matters most.
Fireworks AI
Fast inference with function calling optimization. Strong at serving fine-tuned models and compound AI systems. Good balance of speed, cost, and features for production workloads.
Pricing Models
Pay-per-token (most providers), pay-per-second (some inference), subscription tiers (OpenAI Plus). Input tokens are cheaper than output. Prompt caching (Anthropic, Google) reduces costs for repeated prefixes.
Cost Optimization
Use smaller models for simple tasks (Haiku, GPT-4o-mini). Cache prompts for repeated contexts. Batch non-urgent requests (50% discount). Use open models via inference providers when frontier quality is not needed.
Provider Selection Strategy
Prototype: OpenAI (best docs, widest support). Complex reasoning: Anthropic Claude. Long context: Google Gemini. Budget: Together AI or Groq. Production: start with one, add OpenRouter for fallback.
Inference ProviderService that hosts and runs AI models, offering API access without requiring your own hardware or model management.
Token PricingPay-per-use model where costs are calculated based on number of input and output tokens processed.
Prompt CachingProvider feature that reduces costs and latency by caching repeated prompt prefixes across API calls.
API GatewayUnified access point (like OpenRouter) that routes requests to multiple AI providers through a single API.