By Google DeepMindLondon, United Kingdom6 products across 6 categories
Built for this. Sits inside Gmail, Docs and Drive, so it already has your context. Very large context windows and a generous free tier.
Free plan
Yes
Free tier with generous limits
Month to month
$4.99/mo
Google AI Plus
Billed yearly
$4.17/mo
$49.99 a year, Google AI Plus plan −16%
Watch out: Which underlying model you get varies by tier, and quality varies with it. Plus and Pro were both showing introductory offers when checked — a fraction of the price for the first three months, or a discount on the first year — so the number on the page is not the standing price, and the rows here quote the standing one.
By Khan AcademyMountain View, United States1 product across 1 category
Strong fit. Tutors by asking rather than answering, and stays inside the material rather than wandering. The teacher tools sit alongside the student ones.
Free plan
Yes
Free for teachers in supported regions
Month to month
$4/mo
For you
Billed yearly
$3.67/mo
$44 a year, For you plan −8%
Watch out: Deliberately slower than a chatbot, because it will not simply give you the solution. Tied to Khan Academy content.
All plans (3)
Plan
Price
What you get
Free
$0
Free for teachers in supported regions
For you
$4/mo · $3.67/mo yearly
personalised tutoring on Khan Academy content, writing and debate prompts, career coaching, coding feedback and chat history
For families
$4/mo · $3.67/mo yearly
everything in the personal plan plus child accounts from a parent login, interaction history, moderation alerts and college admissions coaching
Two things separate these and both are on every card.
Fit
Whether a tool is built for this job, a strong fit for it, or
able to do it without that being its focus.
Free plan
Whether there is a tier you can keep using rather than a
trial that expires.
The order
Fit first, then a free plan, then alphabetical. There is
no score, no weighting we decline to publish, and nothing on this site a company can buy.
Questions
What is the best ai for math?
There is no single answer, which is why this page lists 4 rather than one: ChatGPT, Claude, Gemini, Khanmigo. 3 of them are built for this kind of work rather than able to do it. Start with a free one.
Which of these have a free plan?
4 of the 4: ChatGPT, Claude, Gemini, Khanmigo. Free means a real free tier you can keep using, not a trial that expires.
How was this list chosen?
By hand, from the 750 products this site tracks, and it is checked against the catalogue on every build — a product renamed or removed breaks the build rather than quietly disappearing from here. Nothing on this site can be paid for: no listing, no position, no wording.
