Anki Cloze Deletion: How It Works (With Examples)

What is a cloze deletion?

A cloze deletion is a sentence with a blank. Instead of writing a separate question and answer, you take a sentence from your notes and hide the key term. When you review it, Anki shows the sentence with the term replaced by [...], and you try to recall what's missing.

NMDA receptors open only when [...] binds and the membrane is already depolarized.

The answer is glutamate. You didn't have to invent a question: the sentence is the question.

The syntax

Under the hood, a cloze is just text wrapped in double curly braces with a number:

NMDA receptors open only when {{c1::glutamate}} binds and the membrane is already depolarized.

• c1 is the cloze number. Anki makes one card per number.
• Everything after :: and before }} is the hidden answer.

How to create one in Anki

1. Click Add and set the note type to Cloze.
2. Type or paste your sentence in the Text field.
3. Select the word or phrase you want to hide and press Ctrl+Shift+C (Cmd+Shift+C on a Mac).
4. Click Add.

Each time you press the shortcut on a new selection, Anki increases the number (c1, c2, c3…). In recent versions you can add the Alt/Option key to the shortcut to reuse the same number.

One card or several from the same sentence?

The number controls this.

• Different numbers ({{c1::...}} and {{c2::...}}) produce two separate cards from one note. On the first, only the c1 part is hidden; on the second, only the c2 part.
• The same number twice hides both parts on the same card.

Example: {{c1::Glutamate}} binds the {{c2::NMDA}} receptor. gives you one card that asks for glutamate and another that asks for NMDA.

Adding a hint

You can show a hint instead of a bare blank by adding a second :::

{{c1::Glutamate::neurotransmitter}} binds the NMDA receptor.

The card then shows [neurotransmitter] where the answer goes. Use hints when a blank could have several reasonable answers.

Good and bad cloze cards

Too much hidden

Bad: {{c1::Repeated stimulation of a synapse can strengthen signal transmission between neurons.}} The whole sentence is the blank, so there is nothing to anchor your memory.

Better: hide the one idea

Good: Repeated stimulation of a synapse can {{c1::strengthen signal transmission}} between neurons.

Hiding an obvious word

Bad: Long-term potentiation is a {{c1::process}} that strengthens synapses. You'd get this right without knowing anything.

Several unrelated facts in one card

Bad: {{c1::Glutamate}} binds {{c1::NMDA}} receptors, which let {{c1::calcium}} in. If you miss one blank, the whole card fails. Split it into three cards.

When not to use cloze

Cloze is great for definitions, facts, processes and lists of related terms. It's less useful for ideas that need explanation ("why does X happen?"). For those, a normal question-and-answer card usually works better.

Let a tool write the first draft

If you already have notes, writing every cloze by hand is the slow part. Citecards reads your PDF, Word or PowerPoint file, writes cloze cards from it, and shows each one next to the passage it came from so you can check it. You can then edit the text, the notes and the tags, and export a deck that opens straight in Anki.

Frequently asked questions

How many cloze deletions should one card have?

Usually one. If a sentence has several important terms, make a separate card for each (different numbers) so you're never forced to recall everything at once.

Can I use cloze on mobile?

Yes. Cloze notes created on desktop sync to the Anki mobile apps like any other card. Creating them is easiest on desktop, where the keyboard shortcut is available.