Best Free LLM API 2026 — No Credit Card, No Trial Expiry (5 Options Tested)

Tested 5 free LLM APIs in 2026. BazaarLink auto:free routes to zero-cost models automatically — no credit card, no expiry. OpenAI-compatible. Start in 2 minutes.

Getting started with AI development shouldn't cost anything. In 2026, several platforms offer genuinely free LLM APIs — no credit card, no trial expiry. We tested five of them so you can pick the right one and start building in minutes.

Bottom line up front: If you want the fastest path to a working OpenAI-compatible API with no signup friction, BazaarLink's free tier is the easiest starting point. If you need the fastest raw inference speed, Groq wins. If you want the widest model selection, OpenRouter.

Quick Comparison

1. BazaarLink — Best for Zero-Friction Start

BazaarLink provides a free OpenAI-compatible API with no credit card required. The key feature is auto:free — a special model ID that automatically routes your request to whichever capable model is currently available at zero cost. Unlike trial-based free tiers, auto:free keeps working after your signup credits run out.

Free models routed via auto:free include open-weight models from the Llama, Gemma, Qwen, and DeepSeek families. The routing picks the best available option at the time of your request.

Python example

from openai import OpenAI

client = OpenAI(
    base_url="https://bazaarlink.ai/api/v1",
    api_key="sk-bl-YOUR_FREE_KEY",
)

response = client.chat.completions.create(
    model="auto:free",
    messages=[{"role": "user", "content": "Explain transformers in one paragraph"}],
)
print(response.choices[0].message.content)

TypeScript example

import OpenAI from "openai";

const client = new OpenAI({
  baseURL: "https://bazaarlink.ai/api/v1",
  apiKey: "sk-bl-YOUR_FREE_KEY",
});

const res = await client.chat.completions.create({
  model: "auto:free",
  messages: [{ role: "user", content: "Hello" }],
});
console.log(res.choices[0].message.content);

What the free tier includes:

• Free signup credits (no credit card)
• auto:free routing — ongoing zero-cost inference after credits run out
• Full OpenAI SDK compatibility (streaming, function calling, vision)
• Programmatic agent self-registration API
• Taiwan-oriented paid checkout and enterprise billing options, subject to the channel or agreement available at payment time

Note: Want to verify your API provider before committing? Use BazaarLink Probe to test any OpenAI-compatible endpoint for model swapping, token padding, and quality — free.

2. OpenRouter — Best for Model Variety

OpenRouter aggregates hundreds of models from different providers under a single OpenAI-compatible API. The free tier covers a rotating selection of open-source models including Llama 3.3, Mistral, Gemma, and DeepSeek — typically around 20–30 models at any given time.

Rate limits: Free models on OpenRouter typically allow around 200 requests/day per model with a rate limit of 20 requests/minute. Limits vary by model and can tighten during peak hours.

Best for: Developers who want to experiment across many model families before committing. The breadth of the catalog is unmatched. Not ideal if you need a single reliable endpoint — free model availability can vary.

3. Groq — Best for Speed

Groq's custom LPU (Language Processing Unit) hardware delivers the fastest LLM inference available on a free tier — often 10–20× faster than GPU-based providers on equivalent models. This matters for voice AI, real-time chat, and any latency-sensitive pipeline.

Free models: Llama 3.3 70B, Llama 3.1 8B, Mixtral 8x7B, Gemma 2 9B, and others. The lineup updates periodically.

Rate limits: Groq's free tier limits vary by model. Llama 3.3 70B allows around 6,000 tokens/minute and 14,400 tokens/day. Smaller models have higher limits. Check Groq's rate limit page for current numbers as they update frequently.

Limitation: Groq only runs its own curated model selection. No GPT-4o, Claude, or Gemini — if you need those, you need a different provider.

4. Google AI Studio — Best for Gemini Models

Google AI Studio gives free access to Gemini models through a REST API. Gemini 1.5 Flash is the standout free option — it's fast, has a 1M token context window, and handles images natively.

Rate limits: Gemini 1.5 Flash free tier allows 1,500 requests/day and 15 requests/minute. Gemini 1.5 Pro is more restricted on the free tier.

Limitation: The native API uses Google's own format, not the OpenAI standard. There is an OpenAI-compatible endpoint available, but it's partial — some OpenAI SDK features behave differently.

5. Together AI — Best for Fine-Tuning

Together AI offers $25 in free credits on signup — enough for substantial experimentation. It's not a permanently free tier like the others, but the credits go further than most trial offers. The platform's main advantage is fine-tuning support for open-source models, which none of the others offer on a free basis.

Best for: Teams that need to fine-tune Llama or Mistral on custom data before productionizing. For general free inference, the other options last longer.

How to Choose

Getting a Free BazaarLink API Key

Note: No credit card required. BazaarLink's free tier is not a trial — the auto:free model ID gives ongoing zero-cost inference even after your signup credits are used.

Option A: Sign up via web (2 minutes)

1. Go to bazaarlink.ai/free
2. Sign up with email — no credit card
3. Go to /keys and create an API key
4. Set base_url="https://bazaarlink.ai/api/v1" in your OpenAI client

Option B: Programmatic agent registration

AI agents can self-provision a free key in one API call — no human sign-up required:

curl -X POST https://bazaarlink.ai/api/v1/agents/register \
  -H "Content-Type: application/json" \
  -d '{"name": "my-agent"}'

# Returns: {"api_key": "sk-bl-...", "free_model": "auto:free", "upgrade_url": "..."}

Once you have your key, all OpenAI SDK features work identically — streaming, function calling, vision, and embeddings.

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