On October 5, 2026, SemiAnalysis published a study measuring AI subscription plans. It reported that a $200-per-month Claude subscription using Claude Opus 5.5 offers about 5x the "API-equivalent value" of a ChatGPT subscription at the same price using GPT-6.1 Sol. The result assumes agent-style work, in which the model runs multiple processes while using tools, and it reflects conditions after OpenAI reduced the usage allowance for new subscribers to its $200-per-month Pro 200 plan.
However, this "roughly 5x" figure does not mean you can finish five times as much work, or that answer quality is five times higher. It is a value obtained by measuring the number of tokens a plan allows and converting that amount at each model's API pricing. Read alongside both companies' official terms, the picture is that what matters is not only total usage but also how much you can use in a concentrated burst of time, and how allowances differ depending on when you subscribed.
Working backward from usage meters to token consumption
SemiAnalysis's study measured the relationship between tokens, the units in which a model processes text, and how much a subscription plan's usage meter drops.
Even when a subscription shows remaining usage as a percentage, it doesn't tell you how much allowance is consumed by feeding in a long document versus generating a long response. So SemiAnalysis measured new input, generated output, cache writes and cache reads as separately as possible.
A cache stores input that has already been read so it can be reused in later processing. When you keep working while referring to the same documents or code, newly read text and reused cached text cost different amounts. Ignoring that difference would change the estimate of how much you can actually use.
The usage meter doesn't move continuously with every token processed. In the study, SemiAnalysis recorded how many tokens were processed before the display changed by one step, then excluded the incomplete segments left at the start and end to calculate the consumption rate. It repeated the process until the measurement range was within ±5%, and estimated monthly usage from the weekly allowance.
It then applied the ratios of input, output and cache use from SemiAnalysis's own agent-style work in September, and converted each into what it would cost to purchase through the API.
In other words, the relationship between tokens and the usage meter is measured, but the figure for "how many dollars' worth per month" includes assumptions about how the plan is used. The ±5% figure indicates the precision of measuring the consumption rate from the usage meter; it does not mean any user's workload or productivity can be predicted within ±5%. The study should be read as a measurement by a private research firm to compare the usage allowances of each service.
Different API prices mean different converted values for the same number of tokens
Comparing the official API prices of Claude Opus 5.5 and GPT-6.1 Sol in the same units shows a clear price gap.
The following are standard rates for direct API use at standard speed as of October 7, 2026. For GPT-6.1 Sol, the comparison uses the condition of 272,000 input tokens or fewer, where no long-context surcharge applies.
| Token type | Claude Opus 5.5 | GPT-6.1 Sol |
|---|---|---|
| Input | $4 | $2 |
| Output | $20 | $10 |
| Cache read | $0.20 | $0.10 |
Units are US dollars per million tokens. Discounts and regional surcharges are not included.
At standard API rates, Opus 5.5 costs twice as much as GPT-6.1 Sol for input, output and cache reads alike. So even if two subscriptions allowed the same number of tokens, the amount converted to API prices would be larger for Opus 5.5.
This is a property of the "API-equivalent value" metric itself. The higher a model's API price, the larger the converted value of the same quantity of tokens used through a subscription.
If API prices are cut, the API-equivalent value falls even if the amount usable through the subscription doesn't change, because buying the same number of tokens through the API becomes cheaper. For users, that differs in meaning from a cut to the subscription's own allowance.
SemiAnalysis also says that GPT-6.1 Sol's cache read price, half that of GPT-6 Sol, is one factor that pushed its API-equivalent value down.
Furthermore, the same number of tokens doesn't necessarily mean the same amount of text can be processed. In its pricing documentation, Anthropic explains that with the new tokenizer adopted from Claude 4.7 onward, the same text is split into about 30% more tokens on average than under the old tokenizer.
This is not a direct comparison between the Claude and OpenAI tokenizers. Still, it shows that token counts cannot simply be translated into the number of characters you can read or the number of tasks you can finish.
The roughly 5x gap reflects both the amount available through the subscription and the API prices used to put a dollar value on that amount. To compare real productivity, you also need to look at how much input each model must read, how much it must output, and how many retries it takes to finish the same job.
Weekly total usage and what you can use in a short window are separate matters
Claude Pro and Max have a session allowance that refreshes every five hours, as well as a weekly allowance. Even if weekly allowance remains, heavy processing in a short period can hit the five-hour session limit first.
OpenAI's usage limits require some caution. In its October 5 study, SemiAnalysis cited the absence of an Anthropic-style five-hour limit on OpenAI's Pro plan as an advantage. But OpenAI's current official help pages describe five-hour and weekly allowances for Work and Codex, along with mechanisms to refresh them.
It is therefore best to avoid generalizing that "OpenAI Pro has no five-hour limit." The limits that actually apply need to be checked against the current conditions shown for your plan, feature, model and account.
For users who want to push work through all at once, such as before a deadline, the total usable in a week and the amount usable in a few concentrated hours are separate factors in the decision. A high monthly API-equivalent value doesn't help if you repeatedly hit short-term caps and work is interrupted. Conversely, if the total is small, you could use up the allowance midweek even when short-term constraints are looser.
Results also change if you compare different models. SemiAnalysis reports that with a $200-per-month Claude subscription using Claude Fable 5.1, Fable could be used up to an API-equivalent of $2,485, while an OpenAI subscription at the same price using GPT-6 Astra came to $2,897.
In that pairing the API-equivalent amounts are relatively close, so the roughly 5x gap seen between Opus 5.5 and GPT-6.1 Sol cannot be treated as the difference between Claude and ChatGPT as a whole.
Fable also has its own usage conditions. According to Anthropic's official explanation, on Max plans the amount usable on Fable 5 and Fable 5.1 is capped at up to 50% of the overall weekly allowance.
This is not a mechanism that adds 50% on top of the normal weekly allowance. Usage on Fable is deducted from the same weekly allowance. After using the 50% cap on Fable, you can still use the remaining weekly allowance on other models.
On Claude Pro, by contrast, Fable 5 and Fable 5.1 are not included in the subscription allowance, and using them requires pay-as-you-go usage credits.
Allowances for different products also shouldn't be thought of as separate. On Claude, use across the web, Claude Code, Claude Desktop and so on shares the same account allowance. On OpenAI, Work and Codex likewise consume the allowance included in the plan. Users who move between chat, coding and agent work may overestimate how much they can actually use if they assume each has independent capacity.
Pro 200's old allowance stays in place until October 29
OpenAI's official help page for Pro plans describes three Pro plans, at $100, $200 and $500 per month.
It is currently still possible to sign up for Pro 200, but new subscriptions not eligible to carry over the previous terms include a smaller usage allowance than the former Pro 200. The monthly price remains $200.
Based on its own measurements, SemiAnalysis reports that this change halved the token volume available from each model tier. The specific "halving" is SemiAnalysis's measured result; OpenAI's official help says only that the allowance is "less than before." The two need to be treated separately.
A transition period has been set for existing users. Eligible accounts that held an active Pro 200 subscription at any time between September 22, 2026 and 10:00 a.m. US Pacific Time on September 29 can use the previous allowance until October 29, as long as they maintain their Pro 200 subscription.
After October 29, they move to the new allowance, with the monthly price staying at $200. As a result, during October, users with the same Pro 200 name and the same monthly price may be split between those keeping the previous allowance and those on the new one.
Speed settings also need to be matched for a fair comparison. According to OpenAI, compared with using the same model at standard speed, Fast mode consumes the plan's allowance at 2.5 times the rate, and GPT-6 Astra's Ultrafast at 8 times the rate.
This does not mean processing is necessarily 2.5 or 8 times faster. It indicates the multiplier at which the allowance is consumed.
Among individual Pro plans, only the $500-per-month Pro 500 can use Ultrafast. On Pro 100 and Pro 200, Ultrafast is unavailable even if you buy additional credits.
When comparing subscriptions, you need to match not only the monthly price and model name but also which allowance applies and which speed mode is in use. Applying the experience gained under past contract terms directly to a current new subscription could lead to misjudging how much you can actually use.
What to check last: how many of the same jobs you can finish
A plan with a larger allowance is more valuable to users who exhaust their limits and often have work stopped. For people who don't use up their allowance in the first place, whether they can finish the intended work with fewer revisions is more likely to determine satisfaction relative to the monthly fee than the theoretical maximum token volume.
SemiAnalysis's measurements alone do not show whether Claude Opus 5.5 or GPT-6.1 Sol can complete a particular user's work more efficiently.
For a real comparison, it helps to complete the code fixes or document drafting you normally do to the same quality standard, and record the number completed together with how much the allowance dropped. Including the number of revisions and time spent waiting after hitting usage limits also reveals how much the allowance gap changed actual working time.
For example, look not only at "how many tokens you used in a week" but also at "what percentage of the allowance each completed code fix consumed" and "how many retries each finished document took." Recording this over a set period with the same model and settings makes it easier to decide whether to move to a plan with a bigger allowance or switch to a model that finishes work more efficiently.
API-equivalent value is also not a figure for the inference costs AI companies actually bear. It simply multiplies the amount usable through a subscription by the API's selling price, so it cannot be interpreted to mean that "if a user got $3,000 worth of use, the company bore $3,000 in costs for that user."
OpenAI also bills API use separately from ChatGPT subscription plans. The amount usable in a subscription service and the budget for calling the API from your own systems need to be compared under their own separate conditions.
What SemiAnalysis's study showed is that the allowance behind the same monthly price can be compared using token volumes and API prices.
As models, pricing and allowances are updated going forward, what to check is not just how many times larger the API-equivalent amount is. It is important to also measure how many jobs of the same quality you can finish in your own environment. By combining available capacity with the consumption needed to finish each job, you can use the "roughly 5x" figure as one input for choosing the subscription that suits you.