Use ChatGPT and Claude together without losing track of either

Running both ChatGPT and Claude is no longer an unusual setup. The decision has already been made by the time someone searches for how to use them together. What is still open is duller and more useful: which stage of the work goes to which one, how much context has to be re-typed every time the work moves, and where the second window lives so that it can be reached without hunting through twenty tabs.

The comparison posts answer a different question. They rank the two. Ranking does not help a person who has already paid for both, because the ranking changes every few weeks while the shape of the daily work stays the same.

What the two pricing pages say today

Prices and limits are the part of this decision that can be checked rather than argued about. The figures below come from the two vendors' own pricing pages as of 27 September 2026.

Tier	ChatGPT	Claude
Free	$0	$0
Main individual plan	Plus, $20 per month	Pro, $20 per month billed monthly, or $17 per month on an annual plan billed $200 up front
Higher individual plan	Pro, sold above Plus	Max, from $100 per month, at 5x or 20x Pro usage
Team	Business plans listed separately	$20 per seat per month billed annually, $25 billed monthly

Two details on that table are worth reading twice. The first is that Claude's annual plan is billed as a single $200 charge, which makes the monthly figure of $17 a discount that requires a year of commitment rather than a lower monthly bill. The second is that the top ChatGPT tier is currently harder to reach than the price page suggests. OpenAI's own help centre carries a notice that new sign-ups and upgrades to the $200 ChatGPT Pro plan are paused, with existing subscriptions continuing to renew.

On the definition of the middle tier, the help centre is direct:

ChatGPT Plus is a subscription plan that provides enhanced access to the ChatGPT web app for $20/month. Source: help.openai.com

So the realistic cost of running both at the middle tier is $40 per month. That is the number to hold against whatever the second subscription is meant to solve. If the answer is only that one of them writes slightly better prose, $40 is hard to justify. If the answer is that hitting a usage ceiling in the middle of a deadline costs an afternoon, it is easy.

Running both on the free tiers

A no-cost version of this setup exists, and it is more workable than it sounds, because the two free tiers run out in different places.

On the ChatGPT side, the pricing page describes unlimited text chat on the free tier, with caps applied to messages that include uploads, to image generation in both volume and speed, to voice, to deep research, to memory and context, to Codex access, and to the desktop work features. Response speed is also described as subject to bandwidth and availability. The context ceiling for the fast model on the free tier is listed as 27K, which the same page translates as roughly twelve pages of text. The paid tiers raise that to 54K, described as about forty pages, and 128K on the top tier, described as about 250 pages.

On the Claude side, the free tier lists chat on web, desktop, and mobile, web search, file creation and code execution, memory across conversations, connections to outside apps and tools, and artifact creation. The gap to the paid tier is framed as usage volume and access to more capabilities rather than as a different set of basics.

Because the ceilings sit in different places, the two free tiers combine better than two halves of one product. Long documents can go to whichever side handles the file in hand, and high-volume short exchanges to the other. The catch is that the moment one side hits a limit, the work has to move, and moving costs the context. That is acceptable on an ordinary week and a bad idea the day before a deadline.

The sensible upgrade path is therefore a measurement rather than a guess. Run both free tiers for a week, count the number of times work stopped against a ceiling, and note which side it was. One paid subscription usually removes most of those stops, and the second one becomes an easier decision to make or to skip.

Where the overlap actually is

Both products now cover most of the same ground. Both run in a browser, on a desktop app, and on a phone. Both search the web, read uploaded files, run code, hold memory across conversations, and connect to outside tools. The free tier of each is usable for real work rather than being a demo.

That overlap is why a feature-by-feature verdict is unstable. The useful question is not which one is better at a task in general, but which one a given person has already taught. Both improve with a house style: a standing set of constraints, a tone, a list of things never to do. Whichever window holds that context produces better output for that kind of job, and the advantage is specific to the person, not to the model.

This is also why the split usually settles on stages rather than subjects. A writer does not have a "writing task" and a "research task" so much as a sequence: gather, decide, draft, tighten, check. Each stage has a different tolerance for invention, and that tolerance is what should determine the destination.

Split the work by stage, not by verdict

A split that survives contact with a real week tends to look like this.

Divergent stages go to one window, convergent stages to the other. Gathering options, listing angles, poking holes in a plan, and arguing against a decision are divergent. Twenty candidates are better than three, and a wrong candidate costs nothing. Drafting the deliverable, matching a house style, and checking a number against a source are convergent. Here invention is the failure mode, not the point.

Once that line is drawn, the practical rules follow:

• Anything with fixed wording lives in one place. Customer-facing copy, terms, pricing explanations, and anything a legal reviewer has already approved.
• Anything where the answer is not yet known lives in the other. Scoping, first passes at a research question, naming, and design critique.
• Long documents go wherever the context window and file handling suit the file in hand, which is worth testing once rather than assuming.
• Code goes wherever the surrounding tooling is, because the editor and the terminal matter more here than the model's prose.

The reason to write the split down is not tidiness. It removes a decision that otherwise gets made forty times a day, badly, based on which tab happens to be in front.

Carrying context between two windows

The real tax on running both is not the second subscription. It is that thirty minutes of accumulated context in one window does not exist in the other. Copying transcripts across is slow, and the copy is usually worse than the original because it loses the ordering.

Three habits keep that cost down.

Keep the brief outside both tools. One short text file per project holding the goal, the audience, the constraints, the numbers that are already settled, and the things that must not appear. Pasting that at the top of a conversation in either window gets output that is comparable. Without it, the two answers differ because the inputs differed, which teaches nothing about the tools.

Share prompts, not outputs. When a second opinion is wanted, send the same instruction to both and compare the results. Sending a finished draft from one to the other for review sounds efficient, but it anchors the second window to the first one's structure.

Decide how often to double up. Asking both the same question every time doubles the reading. Most work does not need it. Reserve the double pass for decisions that set a direction, then finish in a single window.

One more small habit pays off over months: note which window produced the version that shipped. A single line in the project notes is enough. After a few weeks that record, and not a benchmark, is what settles the split.

The cost nobody prices: finding the window

Two subscriptions create a problem that has nothing to do with either vendor. Both windows stay open all day, buried among mail, chat, a spreadsheet, docs, and the twenty tabs from the last piece of research. The cost of the setup shows up as seconds spent locating the right surface, repeated all day.

The failure has three recognisable forms. Tabs collapse into unreadable slivers, so the target is found by clicking through candidates. Notifications are missed, so a long answer finishes while attention has moved elsewhere and does not come back for twenty minutes. And logins cross, which is the expensive one.

The crossing problem is worth stating plainly. A work Google account and a personal one in the same browser profile means history, memory, and billing can end up attached to whichever session was active. On a shared or company Mac that is a compliance question, not a tidiness question. Neither vendor can fix it, because it is a property of the browser, not of the chat.

Keeping accounts separate without adding windows

There are three ways out, with different costs.

Separate browser profiles are free and work immediately. The cost is that every profile is another window in the app switcher, and switching between six windows is slower than switching between six tabs.

A private window for the second account keeps the sessions apart, but the login goes away every time the window closes, which makes it fine for occasional use and painful for daily use.

A browser that gives each web app its own space keeps cookies isolated per app, so a work account and a personal account of the same service can be signed in at once, each with its own history. The Workspaces page sets out how that grouping works, and Features covers the per-app cookie containers, link routing, and per-app zoom and mute that go with it, along with the keyboard-driven switching that makes the arrangement worth the setup time.

There is more than one product in this category and the free tiers differ a lot in how many apps and spaces they allow, which is the detail that decides whether the free tier is usable at all. Compared with Wavebox lays those conditions out side by side.

What to change first

Write the stage split down, in five lines, and keep the project brief in a file rather than in either chat history. That alone removes most of the friction people blame on the models. Then count how many times in one day the wrong window comes up first. If that number is high, the thing to fix is where the two windows live, which is what a tool like SpaceDeck is for.