xplain.toOpen the app

For papers, textbooks and lecture notes

Highlight anything you read. Watch it explained.

Select a line in any PDF and xplain talks you through it while it draws, like a teacher at a board. Stop it with a question whenever you like.

Put xplain.to/ in front of any arXiv or PDF link. Or open a file from your computer. No account needed.

We call our particular attention “Scaled Dot-Product Attention”. The input consists of queries and keys of dimension dk, and values of dimension dv.

“Each word asks every other word how much it matters.”“Here sat looks hardest at cat.”“The score is a dot product, scaled, then a softmax.”

Three steps, and the hard paragraph makes sense.

  1. 01

    Select what confuses you

    Highlight a sentence, or draw a box around a figure, a table or an equation. PDFs, slides and photos of a page all work.

  2. 02

    Listen and watch

    xplain explains it out loud while it draws on a board. Each drawing appears on the word that names it, like a teacher at a whiteboard.

  3. 03

    Interrupt any time

    Ask by typing or just by speaking. Click anything on the board and ask why it is there. It answers, then picks up where it stopped.

A chatbot gives you a wall of text. xplain gives you the board.

Same question: “what does the derivative at a point mean?”

Chat answer

The derivative f′(a) is defined as the limit of the difference quotient (f(a+h) − f(a))/h as h approaches 0. Geometrically, the difference quotient is the slope of the secant line through (a, f(a)) and (a+h, f(a+h)). As h shrinks, the secant line rotates toward the tangent line, and its slope converges to f′(a), which is the instantaneous rate of change of f at a. For example, if f(x) = x², then (f(a+h) − f(a))/h = 2a + h, which tends to 2a…

xplain
aslope at a = 2a

“Watch the dashed line. As the second point slides toward a, it turns into the yellow tangent. Its slope is the derivative.”

Export the lesson

Download any explanation as a narrated MP4 to rewatch or share with a class.

In your language

The paper can be in English and the explanation in yours.

Any subject

Calculus, transformers, biochemistry, physics. If it is on the page, it can be drawn.

The paragraph you have read five times. Try it now.

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