Four leading AI assistants—ChatGPT, Gemini, Claude, and Copilot—offer free access to their services, making them suitable for everyday tasks. However, each imposes certain restrictions or usage conditions, such as displaying ads, using user data for model training, or providing reduced functionality compared to paid versions. This review covers the free plans and default settings as of early October 2026. All prices are listed in US dollars.

ChatGPT

The free version of ChatGPT provides unlimited text chats powered by GPT-5.6 Luna, along with limited options for file uploads, image generation, voice chats, advanced search, and memory. The new GPT-6 Luna model is available for free only in the desktop app. The context window is 27,000 tokens, roughly equivalent to 12 pages of text, which is about half the size offered by the paid Go ($8/month) and Plus ($20/month) plans.

Since August 2026, ads are shown in Germany for users on free and Go plans. In the European Economic Area and Switzerland, ads are not personalized, and users under 18 do not see them. You can disable ads in the settings by choosing to reduce your message limits, but this also decreases the number of available messages and disables some tools, such as image generation and advanced search.

By default, chats are used to train the model. You can manage this setting in the data management section. For individual requests, you can use a temporary chat, which is not used for training, though a copy is stored for up to 30 days for security reasons.

Gemini

The free Gemini plan includes the Gemini 3.6 Flash model, limited access to 3.1 Pro, advanced search, image generation, and features like Gemini Live, Canvas, and Gems. Paid versions—Google AI Plus ($4.99/month) and AI Pro ($19.99/month)—offer higher limits. According to the Privacy Hub, Gemini chats are not used for advertising purposes.

The main trade-off is data processing and storage. The Keep Activity option is enabled by default for users over 18. Some chats may be reviewed by third-party service staff. Verified chats are stored for up to three years, even after activity is deleted. If Keep Activity is disabled, new chats are saved in your account for 72 hours. For one-off sensitive queries, it’s recommended to use a temporary chat. Skills (Gems), launching in November, will require Keep Activity to be enabled.

Claude

Anthropic has updated its free plan: since September 28, users have access to the Claude Sonnet 5.5 and Haiku 4.5 models. The Opus 5.5 model is only available with a paid subscription (Pro—$20/month or $17/month with annual payment). The free plan includes memory between conversations, artifacts, and connected apps.

Whether chats are used for training depends on the privacy toggle in the settings. After disabling it, new chats are not used for training, but previously used data may remain in training sessions. Chats flagged by the safety filter may be used for internal abuse analysis.

Copilot

Microsoft is gradually reducing the capabilities of the free Copilot. As of August 18, 2026, advanced search is only available by subscription. By default, conversations are stored for 18 months. You can disable model training and memory-based personalization at any time. Personalized ads may use chat history and saved memories, but this can be turned off in the personalization settings. All Microsoft services have a general privacy control switch. Users under 18 do not receive personalized ads in Copilot.

Privacy Settings

All four free plans are suitable for occasional queries. Before entering medical, legal, or corporate data, it’s recommended to review and adjust privacy settings. In ChatGPT and Gemini, data collection is enabled by default. In Copilot, ads may use chat history, while in Claude, you need to manually find and disable the relevant toggle. In Gemini, disabling Keep Activity affects the functionality of skills. For sensitive matters, it’s best to use an assistant with training disabled; for everyday tasks, any of the options will suffice.