10 Free and Paid LLM APIs for Your Next AI Project

Explore 10 free and paid LLM APIs to understand their features. Whether you are building AI applications or coding assistants, discover suitable API options for your needs. Among them, Kimi API offers powerful models for reasoning, coding, and long-context tasks.

13 min readUpdated: 2026-11-14
The best free LLM APIs—Kimi API

Free usage of LLM APIs gives developers a way to test models and prototype AI features before committing to ongoing costs. However, free access comes in different forms, from recurring usage allowances to limited trial credits, each with its own restrictions. Choosing a provider means weighing these conditions alongside model capabilities and the cost of scaling beyond free usage. This guide compares 10 free and paid LLM API options, explaining what each offers, how access is priced, and which projects it suits.

Overview of 10 free and paid LLM APIs

The comparison below covers model providers, multi-provider platforms, and NVIDIA deployment tools. Input formats summarize platform capabilities and vary by model and endpoint; speech, embeddings, and image/video generation may use separate APIs. Access terms were checked on November 13, 2026. A recurring free allowance, an evaluation key, a recharge promotion, and free-to-download software offer different kinds of access.

LLM APISupported inputsKey capabilitiesFree accessKey limitsPaid accessSuitable for
Kimi APIText, images, video, depending on modelReasoning, coding, visual understanding, long-context processingNo permanent free tier; recharge voucher promotion$1 minimum top-up; $5 voucher after $5 cumulative recharge; account rate limits applyUsage-based API pricingLong-document analysis, AI agents, coding assistants
Google Gemini APIText, images, audio, videoReasoning, coding, function calling, embeddingsFree tier on selected modelsModel/project-specific RPM, TPM and daily limitsPay-as-you-go usageMultimodal apps, AI assistants, research tools
GroqCloudText, images, audio, depending on modelFast inference, reasoning, coding, speech processingFree developer tierModel-specific RPM, RPD, TPM, and TPD limitsHigher limits on paid plansReal-time chatbots, voice applications
OpenRouterText, images, depending on modelModel routing, reasoning, coding, provider switchingSelected free model variants20 requests/minute; 50/day, rising to 1,000/day after $10 cumulative credit purchases; failed attempts countPay-as-you-go for paid modelsMulti-model applications, model testing
Cloudflare Workers AIText, images, audio, depending on modelLLM inference, embeddings, image generation, speech processing10,000 free Neurons per day for eligible modelsNeurons measure compute consumption, not requests or tokensWorkers Paid required above the allowance; $0.011 per 1,000 Neurons for excess AI usageServerless AI apps, edge-based chatbots
Mistral AI APIText, images, depending on modelReasoning, coding, embeddings, structured outputsFree mode for Vibe/Studio does not include API accessBilling activation and pay-as-you-go required; model and organization limits applyBilling activation and pay-as-you-go usageAI agents, RAG systems, business applications
NVIDIA API Catalog and NIMText and other model-dependent inputsHosted model APIs, self-hosted LLM inference, optimized model deploymentHosted endpoints for prototyping; NIM and NIM Certified Feature Branch software available at no charge under applicable termsHosted rate limits vary; self-hosted use depends on model licenses and supported GPU hardwareGPU/cloud costs separate; AI Enterprise subscription for Certified Production Branch and enterprise supportPrivate AI deployment, enterprise applications, GPU-accelerated inference
Cohere APIText and images on supported models; audio through a separate APIText generation, embeddings, reranking, retrievalFree evaluation key1,000 trial calls/month; endpoint limits and production approval vary by modelPaid production access; some newer models require sales approvalEnterprise search, RAG, knowledge management
Together AI APIText, images, depending on modelLLM inference, fine-tuning, embeddings, image and video generation through separate APIsNo standard free API trialInitial credit purchase requiredPrepaid usage; $15 minimum first purchase, $5 subsequent top-upsCustom AI models, model experimentation
Novita AIText and other model-dependent inputsLLM inference, image generation, video generation through separate APIsPrevious referral campaign ended; no ongoing free allowance assumedCurrent promotions, if any, must be confirmed in the console; ended referral offer is not a free tierModel-based pricingAI creative applications, multimodal platforms

Note: This comparison is for general reference only. Pricing, free allowances, model availability, features, and usage limits may change and can vary by region, account, and selected model. For the latest information and applicable terms, consult each provider’s official website and documentation before signing up or using its services.

10 free and paid LLM APIs you need to try

With so many LLM API providers available, choosing the right one can take time. To make your search easier, here are 10 free and paid LLM APIs, along with their key features, pricing options, model capabilities, and what they offer for different AI projects and development needs:

Kimi API

Kimi API gives developers access to AI models for advanced reasoning, coding, and long-context processing. It supports OpenAI-compatible API integration, making it easier to connect Kimi models with existing applications and development workflows. Currently, when cumulative top-ups reach $5, users receive a $5 voucher.

API cost: The international kimi-k3.1-pro rate is $2 per million uncached input tokens and $10 per million output tokens, excluding applicable taxes. Cache hits cost $0.20 per million tokens; cache writes cost $2 for a 5-minute TTL or $4 for a 1-hour TTL. These input categories are mutually exclusive. API usage is billed separately from Kimi product subscriptions. See API pricing and cache billing.

Kimi API - Reasoning, coding, and long-context AI models

Key features

  • Advanced reasoning for complex tasks: Handles multi-step questions, analyzes complex information, and connects relevant details to generate well-structured responses. This makes it suitable for research, problem-solving, and applications that require more than basic text generation.

  • AI-powered coding assistance: Helps developers generate code, identify errors, debug issues, explain unfamiliar code, and refine existing implementations across programming languages. It can serve as the foundation for coding assistants and AI-powered development workflows.

  • Long-context understanding: Processes lengthy documents, extensive text, and large codebases while maintaining relevant context. Developers can build applications for document analysis, information extraction, summarization, and context-aware question answering.

  • Multimodal understanding: Supported Kimi models can process visual inputs alongside text, enabling applications to interpret images, screenshots, charts, and other visual information. This expands potential use cases beyond text-only AI applications.

  • OpenAI-compatible API integration: Supports the OpenAI API format, allowing developers to use compatible SDKs and familiar integration workflows. This simplifies connecting Kimi models to existing applications and experimenting with different AI-powered features.

Ideal for

  • Building AI-powered applications and chatbots

  • Developing coding assistants and automation tools

  • Analyzing large documents and datasets

  • Creating AI agents that need reasoning and problem-solving capabilities

Get started with Kimi API

Follow these four steps to create a Kimi API account, fund it, configure access, and verify a first request. The example uses the international API platform and a sample return-policy question.

Step 1. Create a developer account

Visit the Kimi API platform and sign up for a developer account. Log in to access the API console, where you can manage your API keys, usage, and billing.

Create a developer account

Step 2. Generate an API key

Open the API key management section in the console and click Create API Key. Enter a name to identify your key, confirm its creation, and copy the generated key.

Keep your API key secure. Store it in a server-side environment variable or secrets manager, and never expose it in public repositories or client-side code.

Generate an API key

Step 3. Activate and configure your API access

Before making your first API call, add credits to your account. The minimum initial top-up is $1. Then check your account balance, available model access, and applicable rate limits in the console.

This example uses the international base URL https://api.moonshot.ai/v1 and model kimi-k3.1-pro. Use an API key from the matching platform account. Set the key in a Bash-compatible terminal on macOS or Linux; on Windows, use a Bash environment such as WSL for these commands:

export MOONSHOT_API_KEY="YOUR_KIMI_API_KEY"

Run the next request in the same terminal so it can read the environment variable. Never put a live API key in public examples or frontend code.

Step 4. Send your first API request

Once your account is funded and your API configuration is ready, send a test request to verify the connection. For example, you can use a customer service scenario to test how Kimi handles a simple question about a return policy.

This Bash/cURL example sends the sample return policy and the customer's facts to Chat Completions. It uses reasoning_effort: "low" for this simple test:

curl https://api.moonshot.ai/v1/chat/completions \ -H "Content-Type: application/json" \ -H "Authorization: Bearer $MOONSHOT_API_KEY" \ -d '{ "model": "kimi-k3.1-pro", "reasoning_effort": "low", "messages": [ { "role": "system", "content": "You are a customer service assistant. Answer briefly using only the provided sample return policy. If relevant information is missing, ask for it rather than assuming it." }, { "role": "user", "content": "Sample return policy: Customers may return unused items in their original packaging within 30 days of delivery. A customer received an item 10 days ago. It is unused and still in its original packaging. Is the customer eligible for a return under this policy? Explain briefly." } ] }'

The API returns a JSON response containing the model's answer in choices[0].message.content. A successful response confirms that your API key, endpoint, and model configuration work for this basic request. You can then adapt the example by replacing the test prompt with your own application instructions and customer data.

Google Gemini API

Google Gemini API allows developers to connect Google's AI models to their applications. It supports text, images, audio, and video, making it useful for building applications that work with different types of content. Developers can use it for content generation, data analysis, coding, and more. It also provides access to different Gemini models based on project requirements. The Gemini free tier covers selected models, with quotas shown in AI Studio.

Google Gemini API - Multimodal AI for text, images, audio, and video

Key features

  • Multimodal capabilities: Supports text, image, audio, and video inputs through compatible Gemini models, enabling applications to process different types of content.

  • Long context window: Handles large documents and lengthy conversations in a single request.

  • Function calling: Connects AI models with external tools, APIs, and application functions.

  • Structured outputs: Generates responses in formats such as JSON for easier application integration.

Ideal for

  • Building multimodal AI applications

  • Creating AI chatbots and virtual assistants

  • Analyzing documents, images, and videos

  • Developing AI-powered research and productivity tools

GroqCloud

GroqCloud provides API access to language models running on Groq's specialized Language Processing Units (LPUs). Its inference infrastructure is designed for high-speed processing and low-latency responses. Developers can access multiple supported models through a unified API, with OpenAI-compatible endpoints that simplify integration into existing applications.

Free-tier limits: Groq’s free plan is subject to model-specific request and token usage limits.

GroqCloud - Fast AI inference and low-latency responses

Key features

  • Fast inference: Uses Groq's LPU-based infrastructure to deliver fast inference and low-latency responses.

  • OpenAI-compatible API: Supports familiar API interfaces, making it easier to migrate existing applications.

  • Model selection: Provides access to multiple supported open-weight models.

  • Streaming responses: Streams generated content as it becomes available, improving responsiveness in interactive applications.

Ideal for

  • Building real-time AI chatbots

  • Creating fast coding assistants

  • Developing voice-based AI applications

  • Running applications that need low-latency responses

OpenRouter

OpenRouter is an API platform that connects developers with models from multiple AI providers through a single endpoint. Instead of managing separate integrations for different services, developers can access various models using one API key. It makes comparing models and switching providers easier. This flexibility is useful when testing different models for the same application.

OpenRouter - Unified access to multiple LLM providers

Key features

  • Unified API: Access models from multiple providers through one endpoint and API key.

  • Model selection: Compare and choose models based on performance, features, and pricing.

  • Provider routing and fallback: Supports provider routing and fallback options to improve request reliability when a provider encounters availability issues.

  • Usage tracking: Helps developers monitor API usage and spending across models.

Ideal for

  • Comparing different LLM providers

  • Building applications with multiple models

  • Testing models before choosing a provider

  • Managing AI API integrations from one platform

Cloudflare Workers AI

Cloudflare Workers AI provides serverless access to AI models through Cloudflare's global network. Developers can run inference workloads without managing dedicated GPU infrastructure and integrate AI capabilities directly into applications built with Cloudflare Workers. Its model catalog includes options for text generation, embeddings, image generation, and other AI tasks.

Cloudflare Workers AI - Serverless AI model inference

Key features

  • Edge-based inference: Runs supported AI models across Cloudflare's global network, bringing inference closer to applications and users.

  • Serverless deployment: Executes AI workloads without managing dedicated servers.

  • Multiple AI models: Supports models for text generation, embeddings, and image tasks.

  • Workers integration: Connects AI inference with serverless application logic.

Ideal for

  • Building serverless AI applications

  • Adding AI features to existing websites

  • Creating edge-based chatbots

  • Developing lightweight AI-powered tools

Mistral AI API

Mistral AI API provides developers with access to language models designed for text generation, reasoning, coding, and other AI tasks. Its model range includes both general-purpose and specialized options for different workloads. Developers can integrate these models into applications through API requests. It is also a useful choice for teams looking for flexible model deployment options.

Mistral AI API - Models for reasoning, coding, and text generation

Key features

  • Versatile model portfolio: Offers models for general-purpose language tasks, reasoning, coding, and specialized workloads.

  • Function calling: Allows models to interact with external tools and services.

  • JSON outputs: Supports structured responses for application workflows.

  • Embeddings: Provides text embeddings for search, retrieval, and semantic similarity tasks.

  • Agent capabilities: Provides an Agent API with built-in tools such as web search, code execution, and document libraries for building more capable AI workflows.

Ideal for

  • Building AI-powered business applications

  • Creating coding and reasoning assistants

  • Developing retrieval-augmented generation (RAG) systems

  • Automating text processing and content workflows

NVIDIA API Catalog and NIM

NVIDIA API Catalog and NIM offer two ways to access NVIDIA-optimized AI inference services. Developers can use hosted model endpoints in the API Catalog to prototype applications or download NIM containers to deploy supported models on their own GPU infrastructure, including cloud environments and data centers.

Software licensing and compute costs are separate. Current NIM offerings include NIM and NIM Certified Feature Branch at no software charge under applicable terms.

NVIDIA NIM - Optimized AI inference and deployment

Key features

  • Optimized inference: Uses NVIDIA software and GPU technologies to optimize inference performance on supported hardware.

  • Prebuilt containers: Provides preconfigured inference microservices for supported AI models.

  • Standardized APIs: Offers consistent API interfaces for integrating deployed models into applications.

  • Flexible deployment: Supports deployment across cloud, data centers, and workstations.

Ideal for

  • Deploying AI models on GPU infrastructure

  • Building enterprise AI applications

  • Running private AI inference services

  • Integrating generative AI into existing systems

Cohere API

Cohere API focuses on language models and tools designed for business applications and enterprise workflows. It offers capabilities for text generation, semantic search, embeddings, and reranking. These capabilities help developers build enterprise search and retrieval-augmented generation (RAG) systems that retrieve relevant information from large collections of business data. Cohere offers a free evaluation key with a monthly cap and endpoint-specific rate limits.

Cohere API - Enterprise AI, semantic search, and retrieval

Key features

  • Command models: Support text generation, reasoning, and business-focused language tasks.

  • Embed models: Convert text and supported image inputs into vector representations for semantic and multimodal search, depending on the selected model.

  • Rerank models: Improve search results by ranking documents based on relevance.

  • RAG support: Help connect language models with external knowledge sources.

Ideal for

  • Building enterprise search applications

  • Creating retrieval-augmented generation systems

  • Developing knowledge management tools

  • Improving document search and information retrieval

Together AI API

Together AI provides API access to a wide range of open-source and open-weight AI models. Developers can use its platform for text generation, image generation, embeddings, and other inference tasks. It also offers tools for fine-tuning and deploying models. This makes it a flexible option for developers who want more control over their AI model choices.

Together AI API - Open-source model inference and fine-tuning

Key features

  • Extensive open-weight model catalog: Provides access to a broad selection of open-weight models for different AI applications.

  • Fast inference: Provides optimized infrastructure for running AI models.

  • Fine-tuning: Allows developers to customize supported models for specific tasks.

  • Dedicated endpoints: Offers deployment options for applications with specific performance needs.

Ideal for

  • Experimenting with open-source LLMs

  • Fine-tuning models for specific applications

  • Building custom AI chatbots

  • Deploying scalable generative AI services

Novita AI

Novita AI is an AI infrastructure platform that provides API access to a range of language models and generative AI models. Developers can integrate LLM capabilities into applications through hosted API services without managing their own inference infrastructure. In addition to language model access, the platform also offers image and video generation APIs, supporting applications that combine text-based AI with visual content generation.

Novita AI - AI-powered text, image, and video generation

Key features

  • LLM model access: Provides API access to multiple language models for text generation, reasoning, and other language-based tasks.

  • OpenAI-compatible API: Supports compatible interfaces for integrating supported models into existing applications.

  • Hosted inference infrastructure: Provides managed model inference, so developers do not need to operate their own model-serving infrastructure.

  • Additional generative AI APIs: Offers image and video generation models alongside its LLM services.

Ideal for

  • Building AI chatbots and conversational assistants

  • Developing coding assistants and other LLM-powered tools

  • Integrating language models into existing applications

  • Creating AI platforms that combine text, image, and video generation

Which LLM API should you use

Start by choosing the access model that fits your budget. For a prototype without an initial credit purchase, compare eligible Gemini models, Groq's free plan, OpenRouter's free variants, and Cloudflare's daily allowance. Cohere evaluation keys and NVIDIA's hosted catalog are useful for testing under their evaluation or prototyping terms. Kimi, Mistral, and Together require paid API access; Novita's former referral promotion has ended. Then compare the candidates on your own tasks using the factors below.

  • Model capabilities: Choose an API that provides the capabilities your application needs, such as reasoning, coding, text generation, or multimodal processing.

  • Free usage limits: Check the number of free requests, token quotas, rate limits, and whether free credits expire.

  • API compatibility: Look for OpenAI-compatible endpoints and SDK support to simplify integration with existing applications.

  • Response speed: Consider inference speed and latency, especially when building real-time chatbots or interactive applications.

  • Context window: Check the maximum input and output token limits if your application handles long documents or complex conversations.

  • Documentation and developer support: Choose providers with clear API documentation, code examples, SDKs, and troubleshooting resources.

  • Scalability and total cost: Estimate input, output and reasoning usage, cache fees, paid tools, platform charges, and any minimum purchase. For self-hosted NIM, include GPU and operations costs. Compare a complete workload rather than one provider's lowest advertised token rate.

Conclusion

The right API can make AI development easier, more flexible, and more affordable. With so many free and paid LLM APIs for developers, you have plenty of options to experiment with and build something useful. Start with the features that matter most to your project and test different models before making a decision. You can also try the Kimi API to explore its reasoning and coding capabilities.

FAQ

LLM APIs allow applications to communicate with large language models through API requests. Your application sends a prompt or other supported input to the model, which processes it and returns a response. Developers can use these responses to add AI features such as text generation, coding assistance, summarization, and data analysis to their applications.
Choose an API provider based on your project requirements, create an account, and generate an API key. Follow the provider's documentation to configure the API endpoint, select a model, and connect through a compatible SDK or HTTP request. Send a test prompt to verify the integration, and keep your API key secure by storing it in a server-side environment variable or secrets manager.
Yes. Some API platforms provide access to multiple LLMs through a single API endpoint and account. For example, OpenRouter connects developers with models from different providers and offers both free and paid options. You can switch between supported models by changing the model identifier in your API request. However, free model availability, usage limits, and pricing vary.
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