Research & analysis

Study a subject and test yourself

Turn lectures, PDFs and notes into explanations, summaries and practice questions.

Saves half your revision timeBeginnerBest pick: Khanmigo

Best tools for this task

Every pick scored out of 10 on how accurate its output is, how fast it gets you a usable result, and how cheap it is to run. Reorder the list by whichever matters most.

Most accurate

ChatGPT 9.3

Fastest to a result

ChatGPT 9.5

Cheapest to run

Khanmigo 10.0

KH

1. Khanmigo

Best pick
$4/mo learners · free for many teachers

Tutors step by step instead of handing over the answer.

Accuracy
8.7/10
Speed
8.9/10
Cost
10.0/10
GPT

2. ChatGPT

Free · Go $8/mo · Plus $20/mo · Pro $200/mo

Endless practice questions and marking at any difficulty.

Accuracy
9.3/10
Speed
9.5/10
Cost
6.2/10
NB

3. NotebookLM

Free · higher limits in Google AI Pro $19.99/mo

Grounded entirely in your own uploads, with an audio overview.

Accuracy
9.2/10
Speed
9.2/10
Cost
6.2/10

How to do it, step by step

  1. 1

    Upload the course material, not the whole internet — grounding beats generality.

  2. 2

    Ask for a one-page summary, then for ten questions that would catch you out.

  3. 3

    Explain the answers out loud; ask for correction where you were vague.

What usually goes wrong

Check your institution's rules on assisted study before submitting anything.