Best Free AI APIs in 2026

const response = await fetch("https://api.openai.com/v1/chat/completions", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "Authorization": "Bearer YOUR_API_KEY"
  },
  body: JSON.stringify({
    model: "gpt-4o-mini",
    messages: [{ role: "user", content: "Explain quantum computing in 3 sentences" }],
    max_tokens: 200
  })
});
const data = await response.json();
console.log(data.choices[0].message.content);

const response = await fetch("https://api.anthropic.com/v1/messages", {
  method: "POST",
  headers: {
    "x-api-key": "YOUR_API_KEY",
    "anthropic-version": "2023-06-01",
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
    model: "claude-3-5-sonnet-20241022",
    max_tokens: 1024,
    messages: [{ role: "user", content: "Write a Python function to merge two sorted arrays" }]
  })
});
const data = await response.json();
console.log(data.content[0].text);

const response = await fetch(
  "https://generativelanguage.googleapis.com/v1beta/models/gemini-1.5-flash:generateContent?key=YOUR_KEY",
  {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify({
      contents: [{ parts: [{ text: "Compare React and Vue.js for a new project" }] }]
    })
  }
);
const data = await response.json();
console.log(data.candidates[0].content.parts[0].text);

const response = await fetch("https://api.groq.com/openai/v1/chat/completions", {
  method: "POST",
  headers: {
    "Authorization": "Bearer YOUR_GROQ_KEY",
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
    model: "llama-3.1-70b-versatile",
    messages: [{ role: "user", content: "What is the capital of France?" }],
    temperature: 0.7
  })
});
const data = await response.json();
console.log(data.choices[0].message.content);

const response = await fetch(
  "https://api-inference.huggingface.co/models/meta-llama/Llama-3.1-8B-Instruct",
  {
    method: "POST",
    headers: { "Authorization": "Bearer YOUR_HF_TOKEN" },
    body: JSON.stringify({ inputs: "The best programming language for beginners is" })
  }
);
const data = await response.json();
console.log(data[0].generated_text);

const response = await fetch("https://api.mistral.ai/v1/chat/completions", {
  method: "POST",
  headers: {
    "Authorization": "Bearer YOUR_MISTRAL_KEY",
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
    model: "mistral-small-latest",
    messages: [{ role: "user", content: "Write a haiku about programming" }]
  })
});
const data = await response.json();
console.log(data.choices[0].message.content);

const response = await fetch("https://api.replicate.com/v1/predictions", {
  method: "POST",
  headers: {
    "Authorization": "Bearer YOUR_TOKEN",
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
    version: "MODEL_VERSION_ID",
    input: { prompt: "A cyberpunk cityscape at sunset, digital art" }
  })
});
const data = await response.json();
// Poll data.urls.get for the result
console.log(data.id, data.status);

const response = await fetch("https://api.cohere.ai/v1/chat", {
  method: "POST",
  headers: {
    "Authorization": "Bearer YOUR_API_KEY",
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
    model: "command-r-plus",
    message: "Explain the difference between SQL and NoSQL databases"
  })
});
const data = await response.json();
console.log(data.text);