Mercury Edit

Claude

The AI assistant that actually reads the whole document and holds its ground

Free plan

Ask Claude to summarize a 200-page report and it reads all 200 pages. That's not a figure of speech - its 200,000-token context window means you can paste an entire book, a year of emails, or a whole codebase and have a conversation about all of it at once. Most AI assistants quietly drop the earlier parts of long conversations. Claude doesn't. It's also unusually honest. Push back on a correct answer and Claude will explain why it's right rather than softening its position to keep you happy. That quality matters more than it sounds when you're using AI for research, analysis, or anything where you need accurate information more than agreeable information. For writing, Claude consistently produces the most natural-sounding output of any AI assistant - less formulaic, fewer filler phrases, better paragraph rhythm. Anthropic built it with safety and honesty as design constraints, not afterthoughts, and it shows in the day-to-day experience.

ChatGPT

The AI that does everything - text, images, voice, code, browsing, and a thousand integrations

Free plan

ChatGPT is the most widely used AI assistant in the world, and for good reason: it does more things than anything else in this category. Need to generate an image? It's built in via DALL-E 3. Want to have a voice conversation? Advanced Voice Mode works remarkably well. Need to analyze a spreadsheet or run code? The code interpreter handles it. The custom GPT ecosystem is genuinely useful - thousands of specialized assistants built by third parties that you can access directly. If you need a tool that does a very specific thing (analyze contracts, generate social media in your brand voice, tutor you in a specific subject), there's probably a custom GPT for it. The honest tradeoff: ChatGPT is the broadest tool, but not always the deepest on any individual task. For pure writing quality, Claude edges it. For research with cited sources, Perplexity beats it. But if you want one tool that handles everything reasonably well and connects to the widest ecosystem, ChatGPT is the logical default.

Cursor

The AI code editor that edits your whole codebase, not just the line you're on

Free plan

Cursor is what happens when you build an editor around AI rather than adding AI to an editor. It's a VS Code fork, so your extensions and keybindings carry over, but the AI capabilities go significantly deeper than what Copilot can do as a plugin. The standout feature is multi-file editing. Describe what you want changed - "add authentication to all API routes" or "refactor this service to use the repository pattern" - and Cursor identifies every file that needs to change, shows you the diffs, and waits for your approval before applying anything. Getting six out of seven files right on a cross-cutting refactor is genuinely useful work that would take an hour manually. Codebase chat is the other one: ask "where does the user session get invalidated?" or "what does this function actually do?" and get accurate answers based on your actual code, not generic patterns. For joining a new codebase, this alone is worth the subscription price.

GitHub Copilot

The AI coding assistant that works in your editor without asking you to change anything

Free plan

Copilot's biggest selling point has nothing to do with AI quality. It's a plugin. You install it in VS Code, JetBrains, Vim, or whatever editor you already use, and you keep working exactly as before - just with a very good autocomplete that suggests whole functions, not just lines. For developers at companies with strict tool policies, or teams where not everyone is ready to switch editors, this matters enormously. Cursor might be technically more capable, but if half your team won't use it, Copilot's adoption advantage wins. The autocomplete has improved substantially over the past year - function-level completions that are right more often than not, context that understands what you're trying to do across a file. Copilot Chat has closed some of the gap with Cursor for targeted questions. Where it still falls short: you can't ask it to refactor across multiple files, and the chat experience feels bolted-on compared to Cursor's more integrated design. But at $10/month with a usable free tier, it's the obvious starting point for anyone new to AI-assisted coding.