OpenAI's model powers both of these — the difference is packaging. ChatGPT is the standalone assistant; Copilot is the same intelligence threaded through Windows, Edge and Office. Where you work decides which wins.
ChatGPT Plus ($20/mo) is the stronger standalone assistant. Copilot wins only inside Microsoft Office — basic chat is free, and the Office-integrated version comes bundled in M365 Premium ($19.99/mo). Choose by where your work lives.
By OpenAI. Full ChatGPT profile →
By Microsoft. Full Copilot profile →
Best for: Everyday writing, brainstorming, image generation, casual coding
Weakness: Output quality varies between model tiers; pricing tiers can confuse
From $0 (free)/mo. Top tier: $500/mo.
Best for: Excel data, Word drafting, PowerPoint decks, Outlook triage
Weakness: Pro plan is half-useful without an M365 subscription on top
From $0 (free)/mo. Top tier: $99.99/mo.
Pick ChatGPT if you want the full-strength assistant: GPT-5.6 Sol access, image generation, custom GPTs, voice mode and Deep Research. Plus at $20 is simply a more capable product than any Copilot tier.
Pick Copilot if your day happens inside Word, Excel, Outlook and Teams — formula generation, inbox triage and slide drafting where you already work. Basic chat is free; the full Office integration comes with M365 Premium at $19.99/mo (or $199.99/year).
Both at once is common: free Copilot for Office moments, ChatGPT Plus as the main assistant. If you'd only pay for one, pay for the one that matches where you spend your hours.
They share OpenAI models, but the products differ: ChatGPT is a standalone assistant with more features (image generation, custom GPTs, Deep Research); Copilot embeds a lighter version of the same intelligence into Windows and Office.
Basic Copilot chat is free in Windows, Edge and the mobile apps. Office-integrated Copilot requires Microsoft 365 Premium at $19.99/mo (or $199.99/year), with a $99.99/mo Microsoft 365 Pro tier above it — the standalone Copilot Pro plan was discontinued for new signups in 2026.
Copilot, by a wide margin — formula generation, email triage and PowerPoint drafting inside the apps are things ChatGPT can only do via copy-paste.