Medly and Heddy are built for different moments. Medly is an exam-practice platform with AI marking, pitched at GCSE, A-level and beyond; Heddy is a KS3-syllabus tutor for students aged 13 and over that teaches you the idea and refuses to hand over the answer. If your child is in Year 10 or 11 and needs marked exam questions, Medly is the closer fit; if they are 13 or over, still in KS3 or early GCSE, and need to actually understand the work, Heddy is.
Everything about Medly below comes from its own website, read in September 2026. Prices and features change, so treat this as a dated snapshot.
At a glance
| Medly | Heddy | |
|---|---|---|
| Main job | Exam-style practice, AI marking, mocks | Tutoring, then flashcards from the lesson |
| Stages it lists | GCSE, A-level, IB, university | KS3 syllabus, ages 13+ |
| Exam boards | AQA, Edexcel, OCR, WJEC shown | Not exam-board driven |
| Gives the answer? | States it guides rather than tells | Structurally never (worked twin only) |
| Cost | Free to start; £24.99 a month or £180 a year | Free to start; cards free; tutor turns metered |
| Signup | Account needed | No account |
| Platform | Web; its site also lists iOS and Android apps | iOS app |
Medly is ahead on exam practice and marking.
What Medly does better
It marks real answers against exam criteria. Medly's homepage describes essay marking against exam-style criteria, timed full-length mock papers marked question by question, and a bank of more than 6,000 exam-style questions. Heddy has none of that. It does not mark a paper, and it would be wrong to suggest otherwise.
It is organised around the exam boards. Medly shows AQA, Edexcel, OCR and WJEC and a long subject list including Business, Psychology and Computer Science. Heddy covers seven KS3 subjects and stops there.
It has scale and a study plan. Medly says it is used by over 400,000 students, and its homepage describes a daily study plan that works out how many questions a day it takes to hit a target. It also runs free national mocks. Those are real strengths for a student in the middle of GCSE revision.
It says it has a safeguarding team. Medly's own explainer states that DBS-checked safeguarding leads oversee the platform. Heddy's safeguarding is built into the tutors (a fixed Childline line, described here), but it does not have a parent-facing dashboard.
Where they genuinely differ
Age, and therefore the job. The key-stage list on Medly's explainer page begins at GCSE, Years 10 to 11. I found no KS3 listing on the pages I read. A KS3 student is not the audience it describes. That is not a flaw; it is a choice. Heddy is built around that syllabus, on a map of 700 named KS3 concepts and what has to come first (the map is explained here). A Year 8 who is shaky on negative numbers does not need a mock paper; they need someone to notice the gap.
How "not giving the answer" is enforced. Both products say they will not simply hand over answers. Medly's homepage says it "will not write entire essays for you, or instantly give you the answer to assignments, but it will guide you". That is a clear statement of intent. Heddy's version is structural: the function that reveals a hint takes no level argument, the top rung is a worked similar problem followed by "now redo yours", and there is no fifth rung to ask for. I can describe how Heddy enforces its rule because I built it; I cannot see inside Medly and do not claim it fails at its.
Where revision comes from. Medly's practice is a bank of exam-style questions chosen by its adaptive engine. Heddy's revision comes out of your own lessons: the professor who watched you struggle writes the flashcards, which are free and unlimited.
Who sees what. Medly has a parent login on its homepage. Heddy has no parent view of a child's conversations at all, deliberately, and needs no account to open. Some parents will want the first; some teenagers will only try the second.
Price, briefly
Medly says it is always free to start with no credit card, then £24.99 a month or £180 billed yearly (its own page shows £15 a month equivalent). Heddy is free to start; flashcards are free and unlimited, and tutor conversations are metered in Pi Turns (explained here). They are not priced like-for-like, because they sell different things.
Which to choose
Choose Medly if your child is in Year 10 or above, sits GCSEs or A-levels, and needs marked exam-style practice, mocks and a revision plan built around a specific board.
Choose Heddy if your child is 13 or over in KS3, wants understanding rather than marks, and would rather open something tonight without an account or an adult.
They also sit comfortably side by side: Heddy to build the KS3 foundation, a marking platform once papers begin. Heddy is on the App Store if you want to look.
Comparison written 30 Sep 2026 from Medly's public website. Verify current plans and coverage on Medly's own pages. Written by Duke Harewood, who builds the tutors at aitutors.me.
Choose Medly if
- Your child is in Year 10 or above
- They need marked exam-style practice
- You want mocks and a revision plan
Choose Heddy if
- 13 or over, in KS3 or early GCSE
- They want understanding, not marks
- They want no account and no adult
Questions people ask
Is Medly AI free?
At the time of writing (September 2026), Medly's own site says it is always free to start with no credit card, and lists paid plans at £24.99 a month or £180 billed yearly. Check Medly's pricing page for what the free tier includes today.
Does Medly cover KS3?
Medly describes itself as built for GCSE, A-level, IB and university study. The pages I read list GCSE (Years 10 to 11) as the youngest stage, and I found no KS3 listing. Heddy is built around the KS3 syllabus, for students aged 13 and over.
Does Medly give the answer?
Medly states that it will not write entire essays or instantly give the answer to assignments, and that it guides students towards answers. Heddy makes a stricter structural promise: its hint ladder tops out at a worked similar problem, never your own answer.
Can my child use Medly and Heddy together?
Yes, and for a student heading towards GCSEs that is a sensible split. Heddy builds understanding and memory in KS3; a marking-focused platform like Medly earns its place once exam-style papers start.