AI API Free Tiers Compared: What You Can Build for Free
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:
- 15 requests per minute — enough for most development and light production use
- 1 million tokens per minute — handles substantial throughput
- No monthly cap — usage doesn't accumulate and expire
- Both Flash and Pro models — test with the budget model, upgrade to Pro for complex tasks
What You Can Build Free on Gemini
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)
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)
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:
- Mistral: European data sovereignty, competitive pricing, strong multilingual support
- Cohere: Best-in-class for RAG and semantic search, purpose-built enterprise features
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)
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)
- Production chatbot — 100-500 requests/day, fully functional
- Content generation tool — blog drafts, social posts, product descriptions
- Code review bot — analyze PRs, suggest improvements
- Document Q&A system — internal knowledge base search
- Classification pipeline — categorize support tickets, emails, content
Free for Prototyping (OpenAI/Anthropic/Mistral)
- MVP validation — build and test a concept before committing to paid APIs
- Hackathon projects — $5 is plenty for a weekend hackathon
- Learning and experimentation — explore different models and prompting techniques
- Personal tools — low-usage utilities for yourself
Free Tier Limitations to Watch
Free tiers come with trade-offs beyond just usage limits:
- Rate limits: Google's 15 RPM means you can't handle traffic spikes
- No SLA: Free tiers don't come with uptime guarantees
- Data training: Some providers may use free-tier data for model training (check ToS)
- Feature restrictions: Some advanced features (function calling, system prompts) may be limited
- No priority: Paid users get priority during high-demand periods
When to Upgrade from Free
You should move to a paid plan when:
- You exceed rate limits — Google's 15 RPM becomes a bottleneck
- You need reliability — production apps need SLAs and consistent performance
- You need advanced features — fine-tuning, higher context windows, batch processing
- Your $5 credit runs out — obvious but worth stating
- You're making money — if your app generates revenue, invest in reliable API access
Ready to estimate paid costs? Use our calculator to see exactly what your usage would cost across all providers.
Try the APIpulse Calculator or Compare Models Side-by-Side