Introduction

Many AI platforms offer free API keys or generous free tiers for Natural Language Processing (NLP) and Large Language Models (LLMs). Leading options include Google AI Studio & Gemini API, OpenAI (with trial credits), Hugging Face Inference API, and Groq. Other notable providers with free access or trials include Mistral AI, Cohere, IBM Watson NLP, Google Cloud NLP API, NLP Cloud, DeepSeek, Kimi (Moonshot AI), and Zhipu AI.

"Platforms like OpenRouter, Hyperbolic, SambaNova Cloud, and Scaleway Generative APIs also provide free credits or trials."

Community initiatives, such as public GitHub lists and services like Free-LLM API by cups.moe, further expand free access. This comprehensive guide explores all available options as of July 2025, helping developers navigate the rapidly evolving landscape of free AI APIs.

1. Leading Platforms with Free Tiers

Several prominent AI platforms offer free access to their Natural Language Processing (NLP) and Large Language Model (LLM) APIs, either through completely free tiers or generous trial credits. These offerings are invaluable for developers, researchers, and hobbyists looking to experiment with, prototype, and integrate advanced AI capabilities.

1.1 Google AI Studio & Gemini API

Google AI Studio and the Gemini API offer a robust and accessible entry point for developers and researchers looking to experiment with and integrate advanced natural language processing (NLP) and large language model (LLM) capabilities without initial financial commitment.

The platform provides access to powerful models including the multimodal Gemini 1.0 Pro, Gemini 1.5 Pro with its extensive 1 million token context window, and the faster Gemini 1.5 Flash As of July 2025, Google AI Studio is highlighted as a key platform providing free access to models like Gemini 2.5.

Model Requests Per Minute Tokens Per Minute Requests Per Day Notes
Gemini API (General) 15 1,000,000 1,500 For testing and development
Gemini 2.5 Flash 10 250,000 250 July 2025 data
Gemini 2.5 Flash-Lite 15 250,000 1,000 July 2025 data
Gemini 2.5 Pro 5 250,000 100 Restricted access
Cloud NLP API (Core) Not specified Not specified Not specified First 5,000 units/month free

Key Features

  • Supports over 35 languages across numerous countries
  • No rate limits "within reason" and no billing surprises
  • User-friendly web-based IDE for quick prototyping

1.2 OpenAI

OpenAI has been a pivotal player in the advancement and popularization of large language models, and it continues to offer avenues for free access to its technologies, primarily through a free tier for its API, which notably includes access to models like GPT-3.5 Turbo80 .

This free tier is designed to allow developers and enthusiasts to experiment with the API, build prototypes, and develop small-scale projects without incurring costs. The availability typically includes "limited monthly credits".

Note: While GPT-3.5 is often featured in free tiers, access to more advanced models like GPT-4 typically requires a paid subscription.

1.3 Hugging Face Inference API

Hugging Face has established itself as a cornerstone of the open-source AI community, and its Inference API offers a significant free tier that democratizes access to a vast repository of pre-trained models, including many powerful LLMs.

The free Inference API allows users to make API calls to thousands of models, covering tasks such as text classification, question answering, named entity recognition, and text generation. The serverless inference option is limited to models smaller than 10GB, with users on the free tier receiving $0.10 worth of inference monthly .

Open-source models Community-driven Rate-limited access

1.4 Groq

Groq has emerged as a significant provider of free AI API access, particularly noted for its high-speed inference capabilities. As of July 2025, Groq offers a free tier that allows developers to experiment with and integrate powerful AI models without incurring costs.

The free usage limit includes 6,000 tokens per minute and 14,000 API calls per day, which is generally sufficient for ordinary users. Groq's infrastructure is built on its proprietary Language Processing Units (LPUs), designed for executing AI models with high speed and predictability.

Supported Models

  • • Llama 3 (8B and 70B)
  • • Mixtral 8x7B
  • • Gemma 7B
  • • Llama 4 Scout

Key Features

  • • High-speed inference
  • • OpenAI API compatible
  • • Real-time AI applications
  • • Developer-friendly setup

2. Other Notable Free API Providers

Beyond the major platforms, a growing ecosystem of other AI service providers offers free access or generous free tiers for their NLP and LLM APIs. These providers often cater to niche requirements, offer unique model specializations, or provide alternative access models.

2.1 Mistral AI

Mistral AI offers a $5.00 credit to get started with their API, and notably, no credit card is initially required . This approach lowers the barrier to entry, allowing developers to test the capabilities of Mistral's models, such as their high-performing Mistral Large.

Mistral 7B (7.3 billion parameters) is available for free via the API, with pricing for higher volume usage set at $0.25 per 1 million input tokens and $0.25 per 1 million output tokens.

2.2 Cohere

Cohere offers trial keys for its API, which come with certain rate limits and are intended for experimentation and evaluation rather than commercial use. This provides an opportunity to test models like Command R+ or Embed for tasks like text generation, summarization, and classification.

2.4 Google Cloud NLP API

Google Cloud Platform offers a comprehensive suite of AI services, including a dedicated Natural Language AI API with powerful NLP capabilities such as entity analysis, sentiment analysis, content classification, and syntax analysis.

The free tier includes the first 5,000 units per month being free for features like Entity Analysis, Sentiment Analysis, Syntax Analysis, and Entity Sentiment Analysis. New users often receive an initial voucher of $300 in credits.

2.5 NLP Cloud

NLP Cloud provides access to a variety of pre-trained NLP models through a unified API. The platform offers a free plan that allows users to get started without providing credit card details.

Pay-as-you-go plan offers $15 initial credit for testing all features without the restrictions of the free tier.

2.6 DeepSeek

DeepSeek AI has made a significant impact by releasing open-source models that demonstrate exceptional proficiency in specialized domains such as programming and mathematics. Several DeepSeek models are accessible via free API tiers provided by various platforms.

Specialized Models

  • • DeepSeek Coder (6.7B)
  • • DeepSeek Math 7B
  • • DeepSeek V3 / V3 0324
  • • DeepSeek R1 Distill

Available Platforms

  • • Cloudflare (AWQ)
  • • OpenRouter
  • • Hyperbolic
  • • Sambanova

2.7 Kimi (Moonshot AI)

Kimi supports inputs of up to 128K tokens, extending to 200K tokens in some mentions. This makes Kimi particularly well-suited for NLP tasks that involve processing and understanding large documents, extensive conversations, or detailed codebases.

Upon registering and logging into the Kimi platform, users can receive an initial balance of 15 RMB to experiment with the API.

2.8 Zhipu AI (GLM Models)

Zhipu AI makes its GLM-4-Flash model available via a free API . The API protocol for GLM-4-Flash is largely compatible with OpenAI's API format, and no credit card is required to get started.

Note: The Zhipu AI website and API documentation are primarily in Chinese, which may present a language barrier for some developers.

3. Platforms with Free Credits or Trial Offers

Many AI platforms provide new users with free credits or time-limited trial periods. This approach allows potential customers to thoroughly test capabilities, evaluate model performance, and assess developer experience before making financial commitments.

3.1 OpenRouter

OpenRouter.ai functions as a unified API platform that aggregates access to a diverse array of AI models from various providers, including Anthropic, OpenAI, Google, Meta, and many others.

Feature Limit
Requests Per Minute 30
Tokens Per Minute 60,000
Tokens Per Day 1,000,000
Supported Models 300+

Unify provides $5 in credits when a payment method is added, allowing access to a wide array of open and proprietary models.

3.2 Hyperbolic

Hyperbolic provides $10 in trial credits, with another source mentioning $1 in free credits. These credits can be used to explore a wide range of models available on their platform.

DeepSeek V3 Llama 3.1 405B Llama 3.3 70B Qwen2.5 72B Hermes 3 Pixtral 12B Qwen Coder Qwen VL

3.3 SambaNova Cloud

SambaNova Cloud offers $5 in credits, typically valid for a limited period such as three months. This credit allows users to experiment with a range of models hosted on the SambaNova platform.

Available Models

• E5-Mistral-7B-Instruct

• Llama 3.1 8B

• Llama 3.3 70B

• Llama-4-Maverick-17B

• Qwen3-32B

• Whisper-Large-v3

• DeepSeek-R1-0528

• DeepSeek-V3-0324

3.4 Scaleway Generative APIs

Scaleway offers 1,000,000 free tokens for its Generative APIs. This generous allocation allows for substantial experimentation with the available models without initial cost.

Model Type Examples
General Language Llama 3.1/3.3 70B, Gemma 3 27B
Coding Qwen2.5 Coder 32B, DeepSeek R1 Distill
Multilingual BGE-Multilingual-Gemma2
Specialized Mistral Nemo 2407, Pixtral 12B

4. Community & Open Source Initiatives

The landscape of free AI APIs is significantly enriched by community-driven efforts and open-source initiatives. These range from curated lists of publicly available APIs to platforms built by the community to provide free or low-cost access to AI models.

Public LLM API Resources

Public GitHub repositories list free and open-source LLM APIs. One notable resource is the `llm-interface/docs/api-keys.md` within the `samestrin/llm-interface` repository.

Featured Providers in Lists

• AI21 Studio

• Anyscale

• Cloudflare AI

• Cohere

• Fireworks AI

• Google Gemini

• Groq

• Hugging Face

Community-run Free API Services

Community initiatives like "Free-LLM API by cups.moe" provide completely free access to common language models without usage restrictions or keyword censorship.

Service Details

  • • 200 free usage credits upon login
  • • Supports GPT-4.1, Claude Opus 4, Qwen3-235B
  • • DeepSeek models available
  • • RPM limit increased from 2 to 4

Note: Community-run services may be unstable and could "disappear at any time"

AI API Ecosystem Flow

flowchart TD A["Developer Needs"] --> B{"Choose Access Type"} B --> C["Direct Platform APIs"] B --> D["Aggregator Platforms"] B --> E["Community Services"] C --> F["Google AI Studio
Free Tier"] C --> G["OpenAI
Trial Credits"] C --> H["Hugging Face
$0.10/month"] C --> I["Groq
6K TPM"] D --> J["OpenRouter
300+ models"] D --> K["Hyperbolic
$10 credits"] D --> L["SambaNova
$5 credits"] E --> M["GitHub Lists
Curated Resources"] E --> N["cups.moe
200 credits"] F --> O["Application Development"] G --> O H --> O I --> O J --> O K --> O L --> O M --> O N --> O style A fill:#e1f5fe,stroke:#1976d2,stroke-width:2px,color:#000 style O fill:#f3e5f5,stroke:#7b1fa2,stroke-width:2px,color:#000 style B fill:#fff3e0,stroke:#f57c00,stroke-width:2px,color:#000 style C fill:#e8f5e8,stroke:#388e3c,stroke-width:2px,color:#000 style D fill:#e3f2fd,stroke:#1976d2,stroke-width:2px,color:#000 style E fill:#fce4ec,stroke:#c2185b,stroke-width:2px,color:#000

Interactive diagram showing the AI API ecosystem flow from developer needs to application development

5. Key Considerations for Free Tiers

While free tiers and trial offers provide excellent opportunities for exploration, it's crucial to understand various factors that can significantly impact project feasibility and developer experience.

Rate Limits and Usage Quotas

Understanding rate limits (RPM, RPD) and usage quotas (TPM) is paramount. Google AI Studio's free tier has limits like 15 RPM and 1,500 RPD, while specific models like Gemini 2.5 Flash might have limits of 10 RPM and 250 RPD.

Consequences of Exceeding Limits

  • • Throttled requests (slowed responses)
  • • Temporary suspension of API access
  • • Unexpected charges if billing linked

Model Availability and Features

Different providers offer varying selections of models, from smaller efficient models to large, powerful models capable of complex reasoning and multimodal processing.

Consider Model Capabilities

  • • Multimodal understanding (text, images, audio)
  • • Context window size (up to 1M tokens)
  • • Language support (35+ languages)
  • • Specialized features (code generation)

Data Privacy and Security

A critical distinction exists between free and paid tiers in data handling. Google explicitly states that prompts and responses via the free Gemini API may be used to train future models.

Best Practices

  • • Never submit sensitive data to free tiers
  • • Use paid plans for commercial applications
  • • Secure API keys in environment variables
  • • Use HTTPS for all API requests

Ease of Access and API Key Generation

Platforms that streamline API key generation significantly lower the barrier to entry. Google AI Studio is frequently cited for its user-friendly approachl.

Platform Requirements

  • • Google AI Studio: Google account only
  • • OpenRouter: Platform account
  • • Cloud providers: May require billing setup
  • • Community services: Various login methods

Choosing the Right Free API: Decision Framework

flowchart TD A["Project Requirements"] --> B{"Data Sensitivity"} B -->|"High"| C["Paid Plans Only"] B -->|"Low"| D{"Usage Volume"} D -->|"Low"| E["Free Tiers"] D -->|"High"| F{"Model Complexity"} E --> G["Google AI Studio
Hugging Face
OpenRouter"] F -->|"General"| H["Groq
Mistral AI"] F -->|"Specialized"| I["DeepSeek
Kimi
NLP Cloud"] C --> J["Google Vertex AI
OpenAI Paid
Cohere Enterprise"] G --> K["Prototyping
Testing
Small Projects"] H --> L["Development
Experimentation"] I --> M["Niche Applications
Specialized Tasks"] J --> N["Production
Commercial Use"] style A fill:#e3f2fd,stroke:#1976d2,stroke-width:2px,color:#000 style K fill:#e8f5e8,stroke:#388e3c,stroke-width:2px,color:#000 style L fill:#e8f5e8,stroke:#388e3c,stroke-width:2px,color:#000 style M fill:#e8f5e8,stroke:#388e3c,stroke-width:2px,color:#000 style N fill:#fff3e0,stroke:#f57c00,stroke-width:2px,color:#000 style B fill:#f3e5f5,stroke:#7b1fa2,stroke-width:2px,color:#000 style D fill:#f3e5f5,stroke:#7b1fa2,stroke-width:2px,color:#000 style F fill:#f3e5f5,stroke:#7b1fa2,stroke-width:2px,color:#000 style C fill:#ffebee,stroke:#d32f2f,stroke-width:2px,color:#000 style E fill:#e8f5e8,stroke:#388e3c,stroke-width:2px,color:#000 style G fill:#e0f7fa,stroke:#0288d1,stroke-width:2px,color:#000 style H fill:#e0f7fa,stroke:#0288d1,stroke-width:2px,color:#000 style I fill:#e0f7fa,stroke:#0288d1,stroke-width:2px,color:#000 style J fill:#fff3e0,stroke:#f57c00,stroke-width:2px,color:#000

Decision framework for choosing the right free API based on project requirements, data sensitivity, and usage volume