You don't need a credit card to start building with AI APIs. Between free tiers, open-source models, and signup credits, there are enough zero-cost options to prototype, test, and even run small production workloads.
Here's every free option available right now, ranked by practical usefulness.
If you are evaluating free paths as a migration stepping stone, keep the pricing comparison and the China developer guide nearby. The cheapest path on paper is not always the easiest path to operate.
Tier 1: Official Free Tiers (No Credit Card Required)
Google AI Studio (Gemini Models)
Google still has the strongest official free tier, but the useful options have shifted toward the Gemini 3.1 family.
| Model | Free Tier | Why It Matters |
|---|---|---|
| Gemini 3.1 Flash-Lite Preview | Free input/output tier | cheap, high-volume agentic work |
| Gemini 3.1 Flash | Free input/output tier | general-purpose fast model |
| Gemini 3.1 Pro | Free input/output tier | stronger reasoning with long context |
| Gemini Embedding | Free input tier | useful for early RAG experiments |
For prototyping and personal projects, this is still hard to beat. Google AI Studio remains the easiest official way to experiment with a modern frontier model family without touching a card.
from google import genai
client = genai.Client(api_key="YOUR_FREE_KEY")
response = client.models.generate_content(
model="gemini-3.1-flash",
contents="Explain quantum computing in simple terms"
)
print(response.text)
Groq (Open-Source Models, Fast Inference)
Groq provides free access to open-source models with extremely fast inference.
| Model | Free Limit | Speed |
|---|---|---|
| Llama 3.3 70B | 30 req/min | ~500 tokens/sec |
| Mixtral 8x7B | 30 req/min | ~480 tokens/sec |
| Gemma 2 9B | 30 req/min | ~750 tokens/sec |
Groq's speed advantage is real. For latency-sensitive applications where you can use open-source models, this is the fastest free option.
Mistral (Le Plateforme)
Mistral offers free API access to their smaller models.
| Model | Free Limit |
|---|---|
| Mistral Small | Limited free tier |
| Codestral | Free for code tasks |
Cloudflare Workers AI
Cloudflare's free allocation is now measured in neurons rather than request counts. The free plan includes 10,000 neurons per day, which is more flexible than a hard “N requests” cap but does mean the effective free volume depends on which model you run.
Tier 2: Signup Credits (Credit Card May Be Required)
OpenAI
New accounts receive limited free credits (amount varies by region and time). After that, minimum top-up is $5.
Anthropic
New API accounts get limited free credits. Minimum top-up is $5 after credits expire.
LemonData
New accounts get $1 in free credits with no credit card required. This covers roughly:
- 2,500 GPT-4.1-mini requests (1K input + 500 output tokens each)
- 150 Claude Sonnet 4.6 requests
- 500 DeepSeek V3 requests
Since LemonData aggregates 300+ models, your $1 credit works across all of them.
Think of signup credits as bridge capital, not a free tier. They are best for testing provider compatibility, not for designing a long-lived free product around them.
OpenRouter
OpenRouter's free tier currently includes 25+ models with a 50-requests-per-day cap. That is enough for experimentation and model scouting, but not something you should mistake for a stable free production plan.
Tier 3: Open-Source Models (Self-Hosted)
If you have a GPU (or a Mac with Apple Silicon), you can run models locally with zero API costs.
Ollama (Easiest Setup)
# Install
curl -fsSL https://ollama.com/install.sh | sh
# Run a model
ollama run llama3.3
# Use as API (OpenAI-compatible)
curl http://localhost:11434/v1/chat/completions \
-d '{"model":"llama3.3","messages":[{"role":"user","content":"Hello"}]}'
Popular Self-Hosted Models
| Model | Parameters | Min RAM | Quality |
|---|---|---|---|
| Llama 3.3 70B | 70B | 48GB | Near GPT-4 level |
| Qwen 2.5 72B | 72B | 48GB | Strong multilingual |
| DeepSeek R1 (distilled) | 32B | 24GB | Good reasoning |
| Mistral Small 3.1 | 24B | 16GB | Fast, efficient |
| Phi-4 | 14B | 12GB | Good for size |
| Gemma 2 9B | 9B | 8GB | Lightweight |
Hardware Requirements
- 8GB RAM: Can run 7B models (Gemma 2, Llama 3.2 3B)
- 16GB RAM: Can run up to 14B models (Phi-4, Mistral Small)
- 32GB RAM: Can run 32B models (DeepSeek R1 distilled)
- 64GB+ RAM: Can run 70B+ models (Llama 3.3, Qwen 2.5)
Mac Studio M4 Ultra with 192GB unified memory can run models up to 400B parameters, making it a viable alternative to cloud GPU instances for development.
Comparison: Which Free Option Should You Use?
| Use Case | Best Free Option | Why |
|---|---|---|
| Prototyping | Google AI Studio | strongest current official free tier |
| Speed-critical | Groq | fastest open-weight inference |
| Production trials | LemonData $1 credit | one key, many model families |
| Privacy-sensitive | Ollama (local) | data never leaves your machine |
| Small edge apps | Cloudflare Workers AI | free neurons + edge runtime |
| Embeddings | Google AI Studio | easiest official free entry point |
Combining Free Tiers for Maximum Coverage
A practical strategy for indie developers:
- Use Google AI Studio for development and testing
- Use Groq for latency-sensitive features (30 req/min)
- Use LemonData's $1 credit for models not available elsewhere (Claude, GPT-4.1)
- Run Ollama locally for unlimited offline inference
This combination gives you access to virtually every major model family at near-zero cost for development, with enough capacity to handle early prototypes.
Free Does Not Mean Production-Safe
Free access is great for:
- prototyping
- smoke tests
- evaluation runs
- editor experimentation
Free access is usually weak for:
- predictable latency
- SLA-backed workloads
- large daily volume
- stable long-term budgeting
That is why teams often start on a free tier and then migrate to a small paid gateway budget once the product survives the prototype stage.
The clean handoff point is simple: once your free setup is blocking shipping decisions more often than it is enabling experiments, it is time to move to a paid path.
At that point, the goal is no longer “stay free.” The goal is “stay flexible without multiplying providers.”
When to Start Paying
Free tiers stop being practical when:
- You need more than ~1,000 requests/day consistently
- You need guaranteed uptime and SLA
- You need models not available in free tiers (Claude Opus 4.6, GPT-4.1 at scale)
- Your latency requirements exceed what free tiers offer
At that point, the most cost-effective path is usually an aggregator like LemonData or OpenRouter, where a small top-up gives you access to hundreds of models without managing multiple provider accounts.
Ready to go beyond free tiers? lemondata.cc gives you 300+ models with $1 free credit on signup. No credit card required.