The AI Judge
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Pay £20 a month for each AI, or only when you use one?

The short version: work out how many times you used an AI last month for something that actually mattered, then divide your monthly fees by that number. If it lands above a couple of pounds a question, you’re paying a subscription like insurance you never claim. Subscriptions win for daily use of a single AI. Paying by usage wins for irregular use, and for anyone who wants more than one AI on the same question.

The sum is easy, which is why it stings: a subscription is around £20 a month. If you want the two or three good AIs on hand — because the same one doesn’t always win — that’s £40 or £60 a month. Roughly £700 a year.

And the question almost nobody asks out loud: how many times did you actually use them last month?

For a lot of people the honest answer is “four or five”. That’s £12 per question, paid in advance, without noticing.

When a subscription is worth it

It isn’t always a bad deal. It clearly pays off if:

  • You use it nearly every day. If it’s a work tool you open several times a day, the cost per use drops to pennies. No argument.
  • You need what only the paid plan includes. Large files, image generation, specialised modes, integrations.
  • One is enough for you. If you always work with the same one and don’t care about cross-checking, subscribe and move on.

If that’s you, you already know it and this article isn’t for you.

When it’s money down the drain

  • When you use it in bursts. Two intense weeks preparing something, then six weeks without opening it. You pay all twelve months regardless.
  • When you pay for several just in case. The most expensive habit of all: three fees to use each a handful of times.
  • When what you want is to cross-check. Subscribing to two AIs to compare answers means paying £480 a year for the privilege of pasting the same question into two tabs.

The free tier nobody mentions in this argument

Before the subscription-versus-usage question, there’s one worth asking: do you need to pay at all?

Every major AI has a free tier, and for a lot of everyday use it’s enough. If you’re paying £20 a month to write emails and summarise articles, the honest advice is to stop paying and see whether you miss it. Most people don’t.

The free tiers stop being enough in fairly specific places: long documents, heavy use in a single sitting, the newest models. And in one more that matters here — you can’t really cross-check on free tiers, because the limits hit exactly when you’re asking the same question three times in a row.

Two months, side by side

The arithmetic is unglamorous, which is the point. Say you keep two subscriptions at about £20 each:

  • A busy month. You use them most days: forty-odd real uses. That’s roughly a pound per use. The subscription is doing its job.
  • A normal month. You use them five times. That’s about £8 per use — and you paid it in advance, in January, for a question you asked in March.

Now the part people skip: the months where you use them once, or not at all. Those don’t average out, because you can’t get them back. Over a year, the cost per useful question is set almost entirely by your quiet months, not your busy ones.

That’s why the intuition “£20 is cheap” is misleading. £20 is cheap per month and expensive per question, and only one of those is what you’re actually buying.

What paying by usage means

It’s the electricity-bill model: you pay for what you use. No monthly fee, no tie-in, no “I didn’t use it this month”.

You top up a balance, each question deducts what it consumed, and you see the exact spend after every one. An ordinary question costs pennies. One with a sixty-page document costs more, because reading sixty pages costs more — and you can see it.

Two consequences that matter:

No end-of-month surprise. There’s no bill that grows on its own: there’s a balance that goes down when you use it and stops when you don’t.

You don’t pay for not using it. Two months without asking anything costs zero. On a subscription, it costs £40.

The part we won’t dress up

Pay-as-you-go isn’t cheaper always. If you ask something every day, a flat subscription will probably work out better. It’s only fair to say it: usage-based pricing wins for occasional or irregular use — which happens to be most people — but not for heavy use.

And it has a real drawback: you have to top up now and then, and that’s friction a monthly fee doesn’t have.

The sum worth doing

Don’t look at the price. Look at last month’s usage:

  1. How many times did you open an AI for something that genuinely mattered? (Not to play with it: to decide or resolve something.)
  2. Multiply by what you pay monthly in subscriptions and divide.
  3. That’s what each useful question costs you.

If the number surprises you, you have your answer.

Where The Judge fits

We don’t sell an AI: we convene several for the same question and a fixed judge delivers a verdict with its confidence level. You pay by usage, with a prepaid balance, no fee and no tie-in.

The fair comparison isn’t “£20 a month versus pennies per question”. It’s this: getting the cross-check of several AIs on your own would take two or three subscriptions and doing it by hand every time. Here that’s what happens on every question, and you only pay for the ones you ask.

If you ask something daily and one AI does the job, subscribe and don’t think twice. If what you have is four important decisions a year and you want to be sure about those four, paying a fee for twelve months doesn’t make much sense.

Frequently asked questions

Is paying by usage always cheaper? No, and it’s only fair to say so: if you ask something every day, a flat subscription will probably work out better. Usage-based pricing wins for irregular use — which happens to be most people.

Can’t I just cross-check on the free tiers? Not really. The limits hit exactly when you’re asking the same question three times in a row, which is the moment you wanted them for.

How do I work out if my subscription pays off? Count how many times last month you opened an AI for something that genuinely mattered, then divide your monthly fees by that number. That’s your cost per useful question.

What does a question cost with usage-based pricing? Pennies for an ordinary one; more if it carries a long document, because reading it costs more. You see the exact spend after each one.

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