Artificial intelligence has completely changed how we create content. From writing blog posts and captions to generating code and social media replies, AI models can now handle it all — and the best part is, you don’t always have to pay for them.
If you’re building an app, running an AI project, or just experimenting with automation, there are a growing number of free and freemium APIs that let you generate high-quality AI content without burning your budget. Let’s explore some of the best APIs you can start using right now.
1. Google Gemini API (Google AI Studio)
Best for: Developers who want reliable, high-quality text generation backed by Google’s ecosystem.
Google’s Gemini API (formerly Bard) delivers fast, coherent text responses using their latest large language models. Through AI Studio, you can test prompts, generate essays, or build chatbots — all with a surprisingly generous free quota. It’s one of the most stable free options currently available.
Highlight: Uses the same backbone as Gemini 1.5 Pro and Flash models.
Website: ai.google.dev
2. OpenRouter
Best for: Trying multiple top models through a single API.
OpenRouter acts as a universal API layer connecting you to models like GPT-4, Claude, Mistral, and Llama 3. Some of them are free or offer daily credits, letting you experiment before paying. It’s flexible, developer-friendly, and perfect if you don’t want to commit to a single provider.
Highlight: One API key, many AI engines.
Website: openrouter.ai
3. Hugging Face Inference API
Best for: Accessing open-source models directly.
Hugging Face offers APIs for thousands of community and enterprise models. You can generate text, summaries, or code using open-source LLMs like Mistral, Falcon, or Zephyr — all through one endpoint. The free tier covers basic usage, with options to self-host if you outgrow limits.
Highlight: Massive choice of open models.
Website: huggingface.co
4. TextCortex API
Best for: Rewriting and improving content tone.
TextCortex’s API is built for marketers, bloggers, and developers who need rewriting, tone-adjustment, summarization, and language transformation. It’s not just about generating — it’s about refining. You get free trial credits to explore all major endpoints.
Highlight: Specialized in text improvement and paraphrasing.
Website: textcortex.com
5. Mistral API (via La Plateforme)
Best for: Cutting-edge open-weights models.
Mistral’s models have gained attention for being fast, accurate, and open. The platform’s API gives you access to models like Mixtral, which can handle creative writing and technical content generation. While the free plan is limited, it’s excellent for early testing.
Highlight: Strong performance for free-tier access.
Website: mistral.ai
6. Cohere API
Best for: Combining generation with classification and embeddings.
Cohere provides a neat suite of APIs for text generation, classification, summarization, and semantic search. The free tier gives you enough monthly credits to prototype chatbots or writing tools before upgrading.
Highlight: Balanced between creativity and structure.
Website: cohere.com
7. Together AI
Best for: Developers experimenting with next-gen models.
Together AI is a collaborative infrastructure that serves open models at scale. It’s one of the few providers offering high-performance inference for models like Llama 3, Mistral, and Zephyr with a small free quota. The API is built with flexibility and performance in mind.
Highlight: Enterprise-grade speed with open model freedom.
Website: together.ai
8. DeepAI Text Generator
Best for: Quick, lightweight content generation.
If you want something simple without setup headaches, DeepAI offers a basic text generation API that’s completely free. It’s not as advanced as Gemini or Mistral, but it’s fast and ideal for short-form outputs, captions, or creative snippets.
Highlight: 100% free and simple to use.
Website: deepai.org
9. AI21 Studio
Best for: Long-form content and professional writing.
AI21’s Jurassic-2 models are known for producing rich, factual text. Through AI21 Studio, you can access APIs for writing, summarizing, and editing — all under a freemium plan. It’s a favorite among developers building editorial tools.
Highlight: High-quality prose generation.
Website: ai21.com/studio
10. Writer API
Best for: Brand-consistent content generation.
Writer’s API goes beyond generic text generation. It lets teams train custom models for tone, terminology, and brand voice — and offers a free trial for testing. It’s best suited for startups and agencies focusing on consistent, on-brand copy.
Highlight: Enterprise-grade control and customization.
Website: writer.com
11. OpenAI (Free via Partners or Demos)
Best for: Classic GPT-based experimentation.
While OpenAI’s official API is paid, several integrations (like OpenRouter or third-party dev credits) offer free GPT-based access for experimentation. It remains one of the most robust solutions for creative and technical content generation.
Highlight: Still the industry benchmark for versatility.
Website: openai.com/api
12. Pollinations.ai
Best for: Free AI image and text generation via URL.
Pollinations.ai is one of the few APIs that’s entirely free and open-source. You can generate images, 3D renders, or text simply by calling its API endpoints or using a prompt-based URL — no account or API key required. It’s fast, flexible, and perfect for projects that need visual or creative AI without setup hassle.
Highlight: 100% free image and text generation with no sign-up.
Website: pollinations.ai
Comparison Table
| API / Platform | Main Use | Free Tier / Credits | API Key Needed | Open Source | Ideal For |
|---|---|---|---|---|---|
| Google Gemini API | Text generation, chat | Generous free quota | Yes | No | Content apps, assistants |
| OpenRouter | Access to multiple models | Daily credits | Yes | No | Developers testing different LLMs |
| Hugging Face | Open model access | Limited public API | Yes | Yes | Researchers, open devs |
| TextCortex | Rewriting, summarization | Trial credits | Yes | No | Marketers, writers |
| Mistral API | Text generation | Limited free tier | Yes | Yes | Builders needing fast open models |
| Cohere | Text + embeddings | Free monthly quota | Yes | No | Chatbots, analytics |
| Together AI | High-speed open models | Small free quota | Yes | Yes | Prototyping open models |
| DeepAI | Quick text & image gen | Unlimited (simple) | No | No | Lightweight use |
| AI21 Studio | Long-form content | Free tier for testing | Yes | No | Editorial & blog tools |
| Writer API | Brand-consistent content | Free trial | Yes | No | Teams & agencies |
| OpenAI | GPT-based content | Partner credits only | Yes | No | Production-grade apps |
| Pollinations.ai | Image & text generation | Fully free | No | Yes | Visual & creative projects |
Final Thoughts
AI content generation is no longer just for big tech companies — it’s for anyone with an internet connection and an idea. Whether you’re building a content assistant, a writing bot, or an entire AI business, these APIs give you the tools to start strong and scale later.
