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AI API Free Tiers Compared: What You Can Build for Free

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Not ready to commit to paid API access? Every major LLM provider offers some form of free tier — but they vary wildly in what you actually get. Some give you generous daily limits, others offer one-time credits, and a few let you build real products without ever pulling out a credit card.

Here's a comprehensive breakdown of every major free tier in 2026, what you can realistically build with each, and when you'll hit the ceiling.

Free Tier Comparison Table

Provider Free Model(s) Free Limit Rate Limit Best For
Google (Gemini) Gemini 2.0 Flash, Gemini 2.5 Pro Unlimited (with rate limits) 15 RPM / 1M TPM Prototyping, side projects
OpenAI GPT-4o mini, GPT-4o $5 one-time credit Varies by tier Testing, small apps
Anthropic Claude Haiku 4.5, Claude Sonnet 4 $5 one-time credit Varies by tier Evaluation, prototyping
Mistral Mistral Small 4, Mistral Large 3 $5 one-time credit Varies by tier Testing, European compliance
Cohere Command R, Command R+ $5 one-time credit Varies by tier RAG, search, classification
Together.ai Llama 3.1 8B/70B, Mixtral $5 one-time credit Varies Open-source models, experimentation

The winner: Google's Gemini API offers the most generous free tier — effectively unlimited usage with reasonable rate limits. Everyone else gives you a $5 one-time credit that runs out quickly.

Google Gemini: The Best Free Tier

Google's free tier is the clear standout. You get access to both Gemini 2.0 Flash and Gemini 2.5 Pro with generous limits:

What You Can Build Free on Gemini

Chatbot (100 req/day) $0/mo
Document summarizer (50 req/day) $0/mo
Code assistant (200 req/day) $0/mo
Classification service (500 req/day) $0/mo

With 15 RPM, you can handle up to ~21,600 requests per day. That's enough for a real product with moderate traffic — not just a prototype.

OpenAI: $5 Credit (Runs Out Fast)

OpenAI gives new accounts a $5 credit. Here's how long it lasts at different usage levels:

$5 Credit Lifespan (GPT-4o mini)

10 requests/day (light testing) ~55 days
100 requests/day (side project) ~5.5 days
500 requests/day (real product) ~1 day

With GPT-4o ($2.50/$10 per 1M tokens), the $5 credit lasts even shorter. OpenAI's free tier is really just for evaluation — you'll need to pay within a week of any real usage.

Anthropic: $5 Credit (Similar Story)

Anthropic also offers a $5 starting credit. Claude Haiku 4.5 at $1.00/$5.00 per 1M tokens stretches further than GPT-4o but still runs out quickly:

$5 Credit Lifespan (Claude Haiku 4.5)

10 requests/day (light testing) ~80 days
100 requests/day (side project) ~8 days
500 requests/day (real product) ~1.5 days

The credit works across all Claude models, so you can test Haiku, Sonnet, and even Opus — but at Opus pricing ($15/$75), the $5 evaporates in minutes.

Mistral & Cohere: $5 Credits

Both Mistral and Cohere follow the same $5 credit model. The main reasons to use their free tiers:

Neither offers a meaningful long-term free tier — these credits are for evaluation only.

Together.ai: $5 for Open-Source Models

Together.ai gives $5 in free credits to access open-source models like Llama 3.1, Mixtral, and others. The pricing is already low (Llama 3.1 8B at $0.18/$0.18 per 1M tokens), so $5 goes further:

$5 Credit Lifespan (Llama 3.1 8B)

100 requests/day ~46 days
500 requests/day ~9 days
1,000 requests/day ~4.5 days

Together.ai is the best option if you specifically want to use open-source models without managing your own GPU infrastructure.

What Can You Actually Build for Free?

Truly Free (Google Gemini)

Free for Prototyping (OpenAI/Anthropic/Mistral)

Free Tier Limitations to Watch

Free tiers come with trade-offs beyond just usage limits:

When to Upgrade from Free

You should move to a paid plan when:

  1. You exceed rate limits — Google's 15 RPM becomes a bottleneck
  2. You need reliability — production apps need SLAs and consistent performance
  3. You need advanced features — fine-tuning, higher context windows, batch processing
  4. Your $5 credit runs out — obvious but worth stating
  5. You're making money — if your app generates revenue, invest in reliable API access

Want an interactive comparison? Try our Free Tier Comparison tool — see how long each provider's free credit lasts at your usage level.

Compare Free Tiers — Interactive Tool or Estimate Paid Costs

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