These are not substitutes, and treating them as one choice is how people waste money. Copilot is an editor and GitHub layer: inline completions, chat beside the file, pull-request review, and a CLI, billed per seat with a monthly credit allowance. ChatGPT is a general assistant that also writes code well.
If you already have a chat subscription, adding Copilot Pro at $10 a month buys the thing chat cannot do: suggestions in the file while you type. If you have Copilot and are wondering whether to drop ChatGPT, do not: Copilot will not summarise a PDF, draft a design doc, or explain an error message from a library you have not opened yet.
The usual setup is Copilot for keystrokes and one $20 chat plan for everything else.
| Dimension | ChatGPT | GitHub Copilot |
|---|---|---|
| Free tier | Free chat with caps on the newest model and on features like image generation | Free plan with limited completions and a small monthly AI credit allowance |
| Pricing | Plus $20/month; higher tiers on the official pricing page | Pro $10/month, Pro+ $39, Max $100; Business $19/user, Enterprise $39/user |
| Long documents | Upload and summarise long files, contracts, and reports in chat | Not built for it; the context is your open files, the selection, and the repo |
| Coding | Writes, explains and debugs code in conversation; no completions in your editor | Inline completions, next-edit suggestions, agent mode, PR review and a CLI; on paid plans completions do not spend credits |
| Web/research | Browsing, search-style answers, and a large connector catalogue | No general web research; it searches your repository, issues, and indexed docs |
| Best for | Writing, research, design discussion, anything outside the editor | Day-to-day code in the editor, repetitive edits, PR triage |
Choose ChatGPT when the question is not about a file you have open. Design discussions, comparing two libraries, reading an RFC, turning meeting notes into a task list, debugging something you can only describe in words: all of that is chat work, and an editor tool is the wrong shape for it. The same applies to anything long. Dropping a 40-page vendor PDF into a chat and asking what the termination clause actually says is a five-minute job; in an IDE assistant it is not a job at all.
It is also the better place to learn. Asking why a pattern is wrong, then following up three times, works better in a conversation than in a completion popup, and pasting a stack trace gets you an explanation rather than a guess at the next line. What you give up is proximity: every snippet has to be copied into the editor, so short mechanical edits are slower than they would be with a completion.
Choose Copilot when the bottleneck is typing, not thinking. Renaming across a module, writing the eighth test in a file that already has seven, converting a callback chain into async, fixing the same lint error in twelve places: that is where completions and next-edit suggestions earn their $10. Chat beside the file helps too, because the editor already knows which file and which branch you mean, so you skip the context-setting paragraph.
Check the billing model before you plan a budget. Since June 2026 Copilot runs on AI Credits billed by token consumption instead of fixed premium requests, so the flat fee buys a credit allowance rather than a request count. Completions and next-edit suggestions stay outside the meter on paid plans, but agent sessions, premium model calls, code review, and the CLI do consume credits. Heavy agent users can blow past the allowance and land on overage rates.
Most working engineers run Copilot plus one chat subscription, and the split is stable: completions while typing, conversation when stuck. Copilot's paid plans let you choose among several models including Anthropic's and OpenAI's, so the editor tool is not locked to one vendor, and switching model for a hard refactor is a dropdown rather than a new subscription.
If you can only pay for one, pay for Copilot when your job is writing code eight hours a day, and pay for ChatGPT when your job is mostly reading, deciding, and writing about code. The second group is larger than it admits, and a $20 chat plan is the better buy for them.
These barely compete: Copilot lives inside the editor and sees your repository, ChatGPT sees what you paste. For code you already own, Copilot removes the copy-paste loop. For design questions, error explanations and anything outside the repo, ChatGPT is the better conversation.
| Free tier | Yes | Yes |
|---|---|---|
| Checked price | Free $0; Go $8/mo; Plus $20/mo; Pro $100 / $200 / $500/mo; Business $20/seat/mo billed annually ($25 monthly, 2 seats minimum) (checked 2026-10-29) | Free $0; Pro $10/mo; Pro+ $39/mo; Max $100/mo; Business $19/seat/mo; Enterprise $39/seat/mo (checked 2026-10-29) |
| Context window | 1,050,000 tokens on GPT-6 Astra (922K max input, 128K max output); GPT-6.1 Sol inside ChatGPT Work defaults to 500K (checked 2026-10-29) | not published |
| Where it breaks | Blocked in mainland China without a proxy or VPN | Usage is metered in AI Credits, which is hard to forecast |
Prices and limits above were read from each vendor's own page on 2026-10-29; they change without notice, so treat them as the shape of the deal rather than a quote. The practical way to choose: run one real task through both free tiers today — one document you actually care about — and keep whichever needed fewer corrections.
No. Copilot is scoped to your editor and repository, so it has nothing useful to say about a PDF, a vendor contract, or a general research question. It also knows nothing about your branch or the failing test unless you point it at them. It replaces the completion half of your workflow, not the conversation half.
No. GitHub moved every plan to usage-based AI Credits in June 2026, billed by tokens at each model's rate. Code completions and next-edit suggestions stay free of credits on paid plans; agent sessions, premium models and code review consume them. Annual subscribers stayed on the old request terms until renewal.
Copilot Pro is $10 a month and ChatGPT Plus is $20, so $30 covers both halves. If that is too much, keep Copilot Pro and use a free chat tier for research, or the reverse if you code less than you write. A trial week on the free tiers will tell you which half you actually use.