AI code editors
Two questions decide most of it: can you change editor, and do you need suggestions as you type. This page turns them into a rule you can apply in a minute, shows where three well-known tools actually run today, and says what the speed studies do and do not support.
Published by ZeroTwo, which sells a chat workspace, not an editor.
The rule, in priority order
Gate 1. If you must stay in a specific editor:
An extension in the editor you already use
Gate 2. If you need suggestions as you type, or you only want line-level help:
Completion-first: an extension, or an AI-first editor if you are free to move
Then. If you want the AI to edit a few files while you watch:
An AI-first editor, or an extension with an agent or edit mode
Then. If you want to hand over a ticket and review the result later:
A task agent (terminal, web or background) beside your editor
The first matching rule wins. The next section lets you try it.
Hard constraints come first and cannot be outvoted by a score. Only when no constraint applies does the amount you want to delegate pick the surface.
Result, rule 3 of 4
An AI-first editor, or an extension with an agent or edit mode
You stay in the file, read each diff and steer. The surface matters less here than how well it handles your repository, which only a test on your own code can tell you.
This chooses a kind of surface. It does not name a winner, because ZeroTwo has not run a matched task test of editors.
These are invented to show the rule. They are not test results and not real people. Each result below is computed from the answers shown, by the same code that drew the panel above.
Rule 1 fires
An extension in the editor you already use
You still want multi-file edits: use the extension’s agent or edit mode, and read every diff.
Rule 2 fires
Completion-first: an extension, or an AI-first editor if you are free to move
Rule 4 fires
A task agent (terminal, web or background) beside your editor
Rule 2 fires
Completion-first: an extension, or an AI-first editor if you are free to move
You also want ticket-sized hand-offs: run a task agent beside your editor where your policy allows it.
The rule picks a surface. It says nothing about how closely to check what comes back. Evaluate supervision and review requirements before you let any of them near production code.
An earlier version of this page added five 1 to 5 scores and read the sum off a table.
Adding unlike axes hides the one that matters. A high need for typing-speed completion pushed the total up, and the table sent high totals to a terminal agent, which cannot give you completion at typing speed. One worked example also totalled 11 and then recommended a different surface from the one the table assigned to 11.
A constraint is a yes or no. If your team mandates one editor, no amount of enthusiasm for delegation changes that, so the rule asks about constraints first and lets the preference for delegation decide only what is left.
A brand is not a category. Each of these three is listed by its own vendor on more than one surface, so “Cursor is an editor” or “Claude Code is a terminal tool” leaves out half of what the vendor says. Pick the surface, then check the product.
| Product | Surfaces the vendor lists | Our reading |
|---|---|---|
| Cursor | A desktop app and a command-line interface. The page also describes working from Slack and reviewing pull requests in GitHub. | AI-first editor (rules 2 and 3) and task agent (rule 4) |
| Claude Code | Terminal, web, iOS, Android, GitHub, Slack, plus native extensions for VS Code and JetBrains IDEs. | Task agent (rule 4), and an extension inside VS Code or JetBrains, so it can also serve a team locked to those editors (rule 1) |
| GitHub Copilot | Editors including VS Code, Visual Studio, JetBrains IDEs, Xcode, Neovim and Eclipse. The page also describes use in the terminal, on the desktop and on GitHub. | Extension across many editors (rules 1 to 3), with task-level work from GitHub (rule 4) |
Surfaces are quoted as each vendor lists them on its own product page, read on 5 October 2026. Vendors change these pages, so check before you decide. Other AI editors and extensions exist, including Windsurf, Zed and Continue; we have not described them here and make no claim about them. Prices and free-tier quotas are left to the vendors’ own pricing pages because they change.
Three figures get quoted constantly, and one later update changes how to read them. They answer different questions, and none compares one editor with another.
55.8%faster
95 professional developers, all already familiar with JavaScript, were timed writing an HTTP server. Those with GitHub Copilot averaged 1 hour 11 minutes against 2 hours 41 minutes without. GitHub’s write-up rounds it to 55% and reports a 95% confidence interval of 21% to 89%.
A small, fresh, well-specified task. Read at GitHub and arXiv.
19%longer
16 experienced open-source developers worked 246 real issues in repositories they knew well, each issue randomly assigned to allow or forbid AI. Tools were mainly Cursor Pro with Claude 3.5 and 3.7 Sonnet. Allowed AI, tasks took 19% longer.
METR’s own page now carries a notice that these results are out of date. Read at METR.
24% and 20%
The same developers expected AI to make them 24% faster. After the trial, having been slowed down, they still believed it had made them 20% faster.
METR called its newer data an unreliable signal
A second study started in August 2025. METR wrote that developers who did not want to work without AI were dropping out, which likely biases the estimate against AI, and that it believes developers are more sped up in early 2026 than in early 2025. Its raw estimates of the change in task time were -18% for returning developers and -4% for new ones (a negative number means less time), and both intervals include no change.
Read at METR.
Switching has costs the demo does not show. Five checks, in the order they usually bite.
List the language servers, debuggers, linters and extensions your project cannot work without, and check each one runs in the candidate editor. A missing one is a stop, not an inconvenience.
Find out whether code may be sent to the vendor’s servers, which models are allowed, and who approves a new tool. Settle this before you spend a week on the trial.
Pick a task you already know the answer to, such as a closed bug. A demo project tells you about the demo; your repository tells you about your conventions and your build.
Do the same task in your current editor with its AI extension, or without AI. Write down time, how much of the diff you kept, and how much of it you could explain.
Leave the old editor installed with its settings intact until you have finished real work in the new one. Switching back should cost minutes, not a weekend.
Free tiers and open-source editors exist, but their limits change and are not comparable like for like. We have left vendor numbers out; these are the questions that make any free tier comparable.
ZeroTwo is not an editor and does not complete code inside your files. It is a chat and agent workspace you keep next to one, with access to 60+ models, so a question that needs a different model than your editor ships with does not need a different subscription. See the ZeroTwo code agent and the model list.
$0/mo
No card required
$14.99/mo
$11.99/mo billed annually
$29.99/mo
$26.99/mo billed annually
Highlights only. The pricing page lists every plan and allowance.
ZeroTwo publishes this page and sells a chat workspace, so read the framing with that in mind. We did not run a task-by-task test of editors for it. It contains a decision rule we wrote, vendor surfaces read from each vendor’s own product page, and study results read at the publisher, all checked in October 2026. Where we could not check something, we left it out or pointed you to the vendor.
An editing environment where AI completion, chat and agent actions are part of the main interface. The line is blurry: one vendor can ship an AI-first editor, an extension, a command-line tool and a hosted agent, as the table on this page shows. Decide by the surface you will actually work in, not by the product category.
Only if you are free to. If your team or toolchain requires a specific editor, the rule on this page stops at an extension in the editor you already use. If you can switch, test the candidate on a branch of your own repository and keep the old editor installed until you have finished a real task in the new one.
It depends on the task, and the evidence is mixed and dated. In a controlled experiment published in 2022 and 2023, developers using GitHub Copilot finished a small JavaScript server task 55.8% faster. In METR’s 2025 trial of experienced open-source developers on their own repositories, tasks took 19% longer with AI, and METR has since said those results are out of date and that its newer data is an unreliable signal. Neither study compares editors.
Several vendors offer free tiers and some tools are open source with bring-your-own-model, but the limits differ and change, so check each vendor’s current page. Ask what the quota counts, what happens when it runs out, and what the vendor does with your code. ZeroTwo’s Free plan is 100 free credits to start plus 20 bonus credits every day you log in, in a chat workspace; it is not editor completion.
Neither is better in general. If you can switch and want the AI built into the editor itself, an AI-first editor belongs on your shortlist. If you must stay where you are, an extension is the only option. This page does not rank them, because ZeroTwo has not run a matched task test.
ZeroTwo is not an editor and does not complete code inside your files. It is a chat and agent workspace you keep next to one, with access to 60+ models. A code agent is included from the Plus plan, and ZeroCode from Pro.
Our broader guide to choosing an AI tool for coding, for when the question is bigger than the editor.
What the code agent in ZeroTwo does, if a task agent beside your editor is where you landed.
ZeroTwo for developer workflows beyond the editor.