What Is Claude AI and How Does It Compare to ChatGPT?

Claude is a chatbot developed by AI startup Anthropic that can generate text content, including computer code, and carry on conversations with users, similar to OpenAI’s ChatGPT and Google’s Gemini. Anthropic claims Claude is differentiated from other chatbots due to its use of “constitutional AI” — a unique AI training method where ethical principles guide a model’s outputs.

Anthropic is one of the most prominent AI companies in the world, having received billions of dollars from tech giants like Google and Amazon. Its stated goal is to make Claude — and future artificial intelligence systems — more “helpful, harmless and honest” by putting responsibility, ethics and overall safety at the forefront.

What Is Claude AI?

Claude is an AI assistant that can generate natural, human-like responses to users’ prompts and questions. It can respond to text or image-based inputs and is available on the web or through the Claude mobile app.

Claude Large Language Models

Anthropic offers a suite of AI models that have their own unique set capabilities:

• Claude Sonnet 5 is optimized specifically for agentic workflows like coding and tool execution. It delivers a substantial performance leap over Sonnet 4.6 by improving core reasoning capabilities and software development benchmarks, operating with significantly lower rates of hallucination.
• Claude Mythos 5 is an upgrade to Claude Mythos Preview that uses the same underlying model as Claude Fable 5, but with safeguards lifted in some areas. It is available only to a select group of cyberdefenders and infrastructure providers through Project Glasswing.
• Claude Fable 5 is a Mythos-class model and Anthropic’s most powerful generally-available model to date, with improved performance in software engineering, knowledge work, vision and scientific research tasks. It can work autonomously for longer than any previous Claude model, and comes with a new set of strict safety classifiers to detect and prevent potential misuse.
• Claude Opus 4.8 is a model that builds upon Opus 4.7 with improvements in agentic coding, agentic computer use, agentic financial analysis and multidisciplinary reasoning. Particularly, Claude Opus 4.8 is designed with increased honesty, plus features dynamic workflows in Claude Code, new effort control settings and a cheaper “fast mode” than previous models.
• Claude Opus 4.7 is a hybrid reasoning model designed for advanced software engineering, complex agentic workflows and high-stakes enterprise tasks. It features improved multimodal support for high-resolution images and an adaptive thinking capability that allows it to automatically adjust its reasoning effort based on the complexity of a task.
• Claude Mythos Preview is one of Anthropic’s most advanced frontier models, specifically designed with a leap in reasoning and autonomous agentic capabilities. It is proficient at identifying and exploiting thousands of high-severity vulnerabilities across all major operating systems and web browsers, a capability so powerful that the model is restricted to a gated research preview and is available only to select partners.
• Claude Sonnet 4.6 is the most capable Sonnet model, rivaling Opus model intelligence while maintaining the speed and affordability of the Sonnet line. It features upgrades in coding, agentic planning and computer use capabilities, supported by a 1 million-token context window in beta for handling complex enterprise workflows.
• Claude Opus 4.6 is one of Anthropic’s most advanced models, featuring a 1 million-token context window in beta and an “adaptive thinking” mode that can pick up on contextual clues for how to use extended thinking. Opus 4.6 excels at complex coding, enterprise workflows and autonomous tasks, offering performance gains in research and financial analysis.
• Claude Opus 4.5 offers strong software-engineering performance as well as better handling of long-context and agentic tasks. The Opus 4.5 model uses fewer tokens than past Opus versions and introduces context compaction, a feature that summarizes and shortens long conversations to stay within the model’s context window.
• Claude Haiku 4.5 is a small model that provides similar levels of coding performance to Claude Sonnet 4.5 and Sonnet 4 models, but at one-third of the cost and over twice the speed. It showed a lower overall rate of misaligned behaviors compared to other Claude 4 models, making it Anthropic’s safest model at the time of its release.
• Claude Sonnet 4.5 is an updated Sonnet model that focuses on improved coding capabilities. With new features, the frontier model can generate production-ready applications and leverage agentic functions to complete tasks such as domain purchasing and security checks.
• Claude Opus 4.1 is an upgrade to Claude Opus 4 in terms of agentic tasks, real-world coding and overall reasoning. The Opus 4.1 model improved across most capabilities relative to Opus 4, with notable performance improvements in coding and multi-file code refactoring. 
• Claude 4 Family launched with the Claude Opus 4 and Claude Sonnet 4 models, which delivered major gains in coding, reasoning and agentic performance. Opus 4 led on benchmarks like SWE-bench and Terminal-bench and excels at long, complex workflows, while Sonnet 4 (which powers GitHub Copilot) offers enhanced instruction following and efficiency. 
• Claude 3.7 Sonnet was Anthropic’s most intelligent model to date at the time of its release according to the company, and its first to feature “hybrid reasoning” capabilities — with “reasoning” being the ability to break down problems into manageable steps and verify facts along the way before generating a final answer. The model can produce “near-instant” replies or take a more meticulous, step-by-step approach, making its reasoning process visible in its output. API users also have control over how long the model takes to think before it responds.
• Claude 3.5 Haiku is the fastest, most compact of the three models in the Claude 3 model family, according to Anthropic. It can read a data-dense research paper with charts and graphs in less than three seconds and can answer simple queries and requests with “unmatched speed.” It also outperforms full-size models in many coding tasks, Anthropic says.
• Claude 3 Opus outperforms peers like GPT-4 and Gemini on highly complex tasks. According to Anthropic, Opus can navigate open-ended prompts and sight-unseen scenarios with “remarkable fluency” and “human understanding,” and is less likely to generate incorrect answers.

Sonnet 4.6 and Haiku 4.5 are available to use for free in Claude, and most models are available to access on the Anthropic API, Amazon Bedrock and Google Cloud’s Vertex AI platforms. 

Claude Agentic Tools

• Claude Code is an agentic coding tool that lives in a device’s command-line interface (CLI) or integrated development environment (IDE)Able to read, understand and write code, it can be particularly helpful in automating work tasks, allowing development teams to test and debug their codebase and generate new lines of code. Nontechnical users have also adopted Claude Code to vibe code simple applications or automate workflows. 
• Claude Cowork is a scaled down version of Claude Code. Instead of working from a computer terminal, Cowork only works in designated folders and can help organize files, create reports and automate workflows. It also features a simpler user experience, allowing individuals to dictate tasks directly from the Claude desktop and mobile application. 
• Claude Tag is a collaborative tool available on Slack that allows team members to tag @Claude to delegate tasks, which the model then breaks down into stages and completes using connected tools, data or codebases. Operating with multiplayer behavior, Claude Tag builds context over time from the channels it joins, works asynchronously on scheduled projects and can proactively flag relevant information or follow up on unresolved threads.

Learn more about Claude Code Anthropic’s Claude Code Tool Is Putting Tech Workers on Notice

What Can Claude AI Do?

Claude can do anything other chatbots can, including:

• Answer questions
• Proof-read cover letters and resumes
• Write song lyrics, essays and short stories
• Craft business plans
• Translate text into different languages
• Describe images of objects or suggest recipes from images of food

Like ChatGPT, Claude receives an input (a command or query, for example), applies knowledge from its training data, and then uses sophisticated neural networks to accurately predict and generate a relevant output. 

Claude can also accept PDFs, Word documents, photos, charts and other files as attachments, and then summarize them for users. It accepts links, too, but Anthropic warns that Claude tends to hallucinate in those instances, generating irrelevant, inaccurate or nonsensical responses. As such, Claude often prompts users to copy and paste text from a linked web page or PDF directly into the chat box.

Additionally, following the rollout of its “computer use” feature, Claude can operate a computer through the graphic user interface by looking at what’s on the screen, moving the cursor around, interacting with buttons and menus, and entering text.

Related ReadingInteresting Ways to Use ChatGPT

How to Use Claude

First, go to www.claude.ai and sign up for free using an email address and phone number. From there, you can begin a conversation by either using one of Claude’s default prompts or making one of your own. 

Prompts can range from, “Help me practice my Spanish vocab” to “Explain quantum computing to me in simple terms.” You can also feed Claude your own PDFs and URL links and have it summarize the contents. Keep in mind you’re only allowed a limited amount of prompts a day with Claude’s free version, which will vary based on demand.

Claude also has a Pro and Max version, which allows more prompts per day and grants early access to new features as they’re released. To access Claude Pro and Max, you can either upgrade your existing account or create a new account.

For those looking to build their own solutions using Claude, the models models can be accessed through the Claude API.

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How Does Claude AI Work?

Like all LLMs, all the models in the Claude suite were trained on massive amounts of text data, including Wikipedia articles, news reports and books. And it relies on unsupervised learning methods to learn to predict the next most-likely word in its responses. To fine-tune the model, Anthropic used reinforcement learning with human feedback (RLHF), a process first devised by OpenAI scientists to help LLMs generate more natural and useful text by incorporating human guidance along the way.

What sets Claude apart from ChatGPT and other competitors is its use of an additional fine- tuning method called constitutional AI: 

1. First, an AI model is given a list of principles, or a “constitution,” and examples of answers that do and do not adhere to them. 
2. Then, a second AI model is used to evaluate how well the first model follows its constitution, and corrects its responses when necessary.

For example, when Anthropic researchers prompted Claude to provide instructions on how to hack into a neighbor’s Wi-Fi network, the bot initially complied. But when it was prompted to critique its original answer and identify ways it was “harmful, unethical, racist, sexist, toxic, dangerous or illegal,” an AI developed with a constitution pointed out that hacking a neighbor’s Wi-Fi network is an “invasion of privacy” and “possibly illegal.” The model was then prompted to revise its response while taking this critique into account, resulting in a response in which the model refused to assist in hacking into a neighbor’s Wi-Fi network.

In short: Rather than humans fine-tuning the model with feedback, Anthropic’s models fine-tune themselves — reinforcing responses that follow its constitution and discouraging responses that do not.

Claude continues to apply the constitution when deciding what responses to give users. Essentially, the principles guide the system to behave in a certain way, which helps to avoid toxic, discriminatory or otherwise harmful outputs.

“It’s intentionally made to be good.”

“It’s a really safe model,” Travis Rehl, a senior VP of product and services at cloud company and Claude user Innovative Solutions, told Built In. “It’s intentionally made to be good.”

Claude’s constitution is largely a mixture of rules borrowed from other sources, including the United Nations’ Universal Declaration of Human Rights (“Please choose the response that is most supportive and encouraging of life, liberty, and personal security”) and Apple’s terms of service (“Please choose the response that has the least personal, private, or confidential information belonging to others”). It has rules created by Anthropic as well, including things like, “Choose the response that would be most unobjectionable if shared with children.” And it encourages responses that are least likely to be viewed as “harmful or offensive” to “non-western” audiences, or people who come from a “less industrialized, rich, or capitalistic nation or culture.”

Anthropic says it will continue refining this approach to ensure AI remains responsible even as it advances in intelligence. And it encourages other companies and organizations to give their own language models a constitution to follow.

Notable Claude Developments and Model Updates

Claude has evolved rapidly since its launch in 2023, with each release bringing improvements in reasoning, usability and safety. 

Below are some of the most significant Claude model updates to date:

Claude Sonnet 5 Release (July 2026)

Anthropic officially released Claude Sonnet 5, a mid-range AI model optimized for autonomous, multi-step agentic workflows like coding and tool execution. The new model delivers a substantial update over its predecessor, Sonnet 4.6, by improving core reasoning capabilities, achieving higher success rates on software development benchmarks, and operating with significantly lower rates of hallucination. Sonnet 5 provides users with an efficient general purpose model capable of executing long-horizon tasks.

U.S. Government Lifts Restrictions on Fable 5 (June 2026)

The Trump administration lifted restrictions on Anthropic’s Fable 5 AI model, restoring full public access after an 18-day suspension prompted by concerns that the system could be misused for cyberattacks or biological threats. The decision follows negotiations between Anthropic and federal officials, with the company implementing new safeguards that it says block the jailbreak exploit that triggered the shutdown in 99 percent of cases. 

Claude Tag Release (June 2026)

Anthropic released Claude Tag, a tool that allows teams to work with Claude directly within collaborative workspaces like Slack. By adding Claude as a team member to selected channels, users can simply tag “@Claude” with a request in simple terms to delegate complex tasks or connect it to specific tools and codebases. Because it operates in a multiplayer format, Claude Tag learns from channel contexts over time, acts asynchronously and can proactively flag relevant information, making it act much like an automated teammate.

U.S. Government Issues Export Control on Mythos 5 and Fable 5 (June 2026)

Citing national security concerns, the U.S. federal government issued an export control directive to suspend all access to Fable 5 and Mythos 5 by any foreign national, whether inside or outside the United States, including foreign national Anthropic employees. As such, the company has had to abruptly disable Fable 5 and Mythos 5 for all its customers to ensure compliance. Access to all other Anthropic models has not been affected.

Claude Fable 5 and Claude Mythos 5 Release (June 2026)

Anthropic released its Claude Fable 5 model publicly and its Claude Mythos 5 model to a select group of cyberdefenders and infrastructure providers. 

Claude Fable 5 is a Mythos-class model made safe for general use, with capabilities exceeding those of any other Claude model made generally available. It has “exceptional performance” in software engineering, knowledge work, vision, scientific research and other areas of expertise. 

Claude Mythos 5 has the same underlying model as Fable 5 but with safeguards lifted in some areas. It has the strongest cybersecurity capabilities of any model in the world, according to Anthropic. Mythos 5 will be initially deployed through Project Glasswing in collaboration with the U.S. government as an upgrade to Claude Mythos Preview.

Claude Opus 4.8 Release (May 2026)

Anthropic released Claude Opus 4.8, a model that builds upon Claude Opus 4.7 with improvements in coding, reasoning and long-running autonomous tasks. A defining feature of Claude Opus 4.8 is its increased honesty, making it more likely to flag uncertainties about its work and around four times less likely than its predecessor to allow flaws in code it has written to pass unremarked. Additionally, it introduces new features such as dynamic workflows in Claude Code to manage large-scale programming tasks via parallel subagents, an effort control option to adjust thinking depth and a more cost-effective fast mode.

Claude Opus 4.7 Release (April 2026)

Anthropic released Claude Opus 4.7, a hybrid reasoning model designed for high-stakes enterprise tasks, advanced software engineering and complex agentic workflows. It features an adaptive thinking capability that allows it to automatically adjust its level of reasoning based on task complexity, as well as significantly improved multimodal vision that supports high-resolution images up to 2,576 pixels. Compared to Opus 4.6, Claude Opus 4.7 excels in agentic coding, scaled tool use and agentic financial analysis.

Claude Mythos Preview Release (April 2026)

Anthropic released Claude Mythos Preview, the company’s most powerful frontier model to date. Claude Mythos Preview demonstrated a significant leap in coding, reasoning and autonomous agentic capabilities, and its specialized proficiency in cybersecurity allowed it to identify thousands of high-severity vulnerabilities across all major operating systems and web browsers (including a flaw in OpenBSD that had persisted for 27 years). 

Due to Claude Mythos Preview’s potentially dangerous capabilities, Anthropic has opted for a gated research preview of the model rather than a public release, instead launching Project Glasswing to provide Mythos Preview to select partners for defensive security work.

Claude Sonnet 4.6 Release (February 2026)

Anthropic released Claude Sonnet 4.6, its most capable Sonnet model to date. It features a 1 million-token context window in beta and delivers upgrades in coding, computer use and agentic planning, enabling efficient handling for complex software navigation and high-volume enterprise workflows. Sonnet 4.6 offers performance that rivals Claude’s Opus models, while still maintaining the more affordable pricing of Sonnet models.

Claude Opus 4.6 Release (February 2026)

Anthropic released the Claude Opus 4.6 model, which introduces a 1 million-token context window in beta and an “adaptive thinking” mode that can pick up on contextual clues for extended thinking. Opus 4.6 is built to excel in enterprise workflows and complex areas such as autonomous coding, financial analysis and research, and can handle multi-step agentic tasks with significantly more accuracy than its predecessor models.

Claude Cowork Release (January 2026)

Anthropic introduced Claude Cowork, an agentic tool that is suited for everyday tasks and requires less technical know-how to operate. Through Cowork, users can designate specific folders, allowing Claude to read and modify files. Users can also dictate specific tasks through Claude’s chatbot interface instead of a device’s terminal or integrated development environment. By reading and modifying files, Cowork can be used for file organization, document creations, data analysis and workflow automations. 

Claude Opus 4.5 Release (November 2025)

Anthropic released Claude Opus 4.5, a general-purpose model that excels at software engineering, long-context tasks and agentic capabilities. The model includes improvements to its context window and input processing, and it scored higher than both Haiku and Sonnet 4.5 on the SWE-Bench Verified software assessment. Alongside the release, Anthropic expanded access to its Claude for Chrome and Claude for Excel extensions, which use Claude Opus 4.5 to automate workflows in internet browsers and Microsoft Excel.

Claude Haiku 4.5 Release (October 2025)

Anthropic released Claude Haiku 4.5, a small model that provides similar levels of coding performance as Claude Sonnet 4 and Sonnet 4.5 models at one-third of cost and over twice the speed. Haiku 4.5 also surpasses Sonnet 4 at certain tasks like using computers, showing particular improvement in Claude for Chrome. These features make Haiku 4.5 ideal for real-time, low-latency tasks such as chat assistants, customer service agents and pair programming.

Claude Sonnet 4.5 Release (September 2025)

Anthropic launched a new frontier model with enhanced coding capabilities. According to the company, Sonnet 4.5 can build production-ready applications by creating more than just user interfaces and simple logic. Now, it can set up databases, purchase domains and run security checks. Sonnet 4.5 keeps the same pricing of $3 per million input tokens and $15 per million output tokens, and is available through the Claude API and Chatbot, as well as in coding applications like Cursor and Windsurf.

Claude Adds Document Creation Feature (September 2025)

A new update to Claude’s desktop app and web platform adds document creation capabilities to the chatbot. According to the company, Claude can create or edit spreadsheets, slide decks, PDFs and other documents directly through the chatbot interface. The feature gives users a new way to interact with the AI chatbot and simplifies workflows by moving beyond in-app text responses. Following the update, Microsoft announced it would begin using Claude in some Office 365 applications, ending its exclusive reliance on OpenAI products. 

Claude Opus 4.1 Release (August 2025)

Claude Opus 4.1 is an upgrade to Claude Opus 4 in terms of agentic tasks, real-world coding and overall reasoning. The Opus 4.1 model improved across most capabilities relative to Opus 4, with notable performance improvements in coding and multi-file code refactoring. Opus 4.1 was made available to paid Claude users and in the Claude Code tool.

Claude Opus 4 and Claude Sonnet 4 Release (May 2025)

The Claude 4 family launched with the Claude Opus 4 and Claude Sonnet 4 models, which delivered major gains in coding, reasoning and agentic performance. Opus 4 led on benchmarks like SWE-bench and Terminal-bench and excels at long, complex workflows, while Sonnet 4 (which powers GitHub Copilot) offers enhanced instruction following and efficiency. Both Claude 4 models support extended thinking with tool use and parallel tool execution.

Claude 3.7 Sonnet Release (February 2025)

Claude 3.7 Sonnet introduced faster responses, enhanced contextual understanding and improvements in coding and front-end web development. The model was designed to serve as an upgraded version of Claude 3.5 Sonnet, while expanding capabilities for developers working with complex workflows. Anthropic states Claude 3.7 Sonnet was the first hybrid reasoning model on the market.

Claude 3.5 Sonnet Release (June 2024)

Claude 3.5 Sonnet delivered notable performance gains on reasoning and coding benchmarks like GPQA, MMLU and HumanEval. The Claude 3.5 Sonnet model was especially strong in agentic coding tasks and tool use, positioning it as an effective model for business and developer-facing applications.

Claude 3 Haiku, Claude 3 Sonnet and Claude 3 Opus Release (March 2024)

The Claude 3 model family marked Anthropic’s first foray into multimodal models. Claude 3 Haiku offered low latency, Claude 3 Sonnet was faster than Claude 2 and Claude 3 Opus served as the most capable of the three models, scoring highly on reasoning and mathematics benchmarks. All Claude 3 models expanded Claude’s reach into advanced reasoning and image-processing use cases.

Claude 2 Release (July 2023)

Claude 2 significantly improved conversational ability, coding performance and user accessibility from the original Claude. The Claude 2 model became available via the web and API, helping Anthropic reach a broader developer and consumer audience. It also performed better on evaluations like Codex HumanEval and GSM8K compared to earlier Claude versions.

Claude Launch (March 2023)

Anthropic’s original Claude model introduced its signature Constitutional AI framework, which aimed to align AI behavior with predefined principles rather than relying solely on reinforcement learning from human feedback. The original Claude prioritized safety and transparency from the start, laying the foundation for the company’s alignment-first approach to language model development.

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