How to

Using needspace, start to finish

Everything lives in a simple loop: put what you want to learn into collections of cards, then study whatever is due each day and rate how well you remembered. This page walks through each step with examples.

1 · Create a collection

A collection is a deck of cards about one topic — "Spanish vocabulary", "Anatomy", "Chess openings". On your dashboard, fill in the New collection form: a name, an optional description, and whether it should be public.

Private (the default) — only you can see it.
Public — it gets a shareable page anyone can open, and it appears on the browse page where others can study it too. You can also pick a category (Languages, Science, Math…) on the collection page so people can find it. You can flip a collection between public and private at any time.

2 · Write cards

Open a collection and hit Add card. A card has a front (the question) and a back (the answer), each up to 500 characters:

Front What is the capital of France?

Back Paris

Both sides support a small set of formatting:

# Big heading
**bold**, *italic*, ~~crossed out~~, `code`
- bullet point
1. numbered step

A few extras on the same form:

Images. Attach a picture to either side — a side can even be image-only, with no text. Great for maps, diagrams, or "name this" cards.
Tags. Comma-separated labels (up to 10 per card) to keep a big collection organized, e.g. verbs, irregular.
Also add the reverse. Ticking this creates a second, mirrored card (back as the question, front as the answer) — the classic move for vocabulary, where hola → hello and hello → hola are two different memories. The checkbox stays on while you keep adding cards.
Duplicate warning. If a card with the same front already exists in the collection, the form quietly warns you. It never blocks you — sometimes a repeat is intentional.

3 · Fill-in-the-blank cards

Wrap any part of the front in double braces and the card becomes a fill-in-the-blank (cloze) card:

Front The capital of {{France}} is {{Paris}}

Back (optional — shown as extra context with the answer)

Each pair of braces is its own blank, and each blank is studied as its own card with its own schedule. The example above produces two:

The capital of [ … ] is Paris
The capital of France is [ … ]

While one blank is hidden, the others show their text — they're separate questions, not secrets. Recall the answer in your head, reveal, and rate yourself as usual. Cloze cards skip the reverse option, since a fill-in-the-blank has no meaningful "back to front".

4 · Import a CSV

Already have a word list in a spreadsheet, or a deck exported from another app? On the collection page, use Import CSV. The file needs front and back columns, plus an optional tags column with semicolon-separated tags:

front,back,tags
What is the capital of France?,Paris,geography;europe
hola,hello,greetings
The capital of {{Italy}} is {{Rome}},,geography

Up to 5,000 rows (2 MB) per file. Cloze syntax works in imported cards too. After the import you get a summary of what was added and which rows were skipped and why — nothing fails silently.

5 · Study

Hit Study on a collection, or Study all due on the dashboard to review due cards from every collection in one session. Only cards that are actually due show up — that's the whole point of spaced repetition. Brand-new cards trickle in at a daily limit (20 by default, adjustable per collection) so day one doesn't bury you.

For each card: read the question, recall the answer in your head, press Show answer, then rate yourself honestly:

Again Didn't remember. The card comes back very soon.
Hard Got it, but it was a real struggle. Shorter gap.
Good Remembered with normal effort. The gap grows.
Easy Instant. The gap grows a lot.

That rating is all the scheduler needs — the FSRS algorithm picks the next review date per card, per direction, per blank. Honest ratings matter more than good ones.

Around the card you'll find:

Timer & pause. The session clock pauses when you do; the card blurs while paused so nobody studies off the clock.
Suspend (the moon button) — takes the current card out of rotation until you resume it from the collection page.
Read aloud — the speaker button reads the visible side to you.
Card animation — pick between a plain crossfade and a swipe-away deal animation.
Fullscreen (on phones) — the expand button strips everything but the card, the timer, and the answer buttons.

When the queue is empty you get a summary: time spent, cards reviewed, success rate, and any achievements you just unlocked.

6 · Practice without consequences

The Practice button on a collection starts a cram session: the same card flow, but shuffled, ignoring due dates, and nothing you rate touches your schedule. Use it before an exam, or to warm up a fresh deck — your forgetting curves stay exactly where they were.

7 · Study settings

Each collection has its own study settings (on the collection page), personal to you:

New cards per day — how many not-yet-studied cards may enter the queue daily (default 20).
Desired retention — the recall probability the scheduler aims for (default 90%). Higher means more frequent reviews; lower means fewer reviews and more forgetting. 85–95% is the sensible range.
Also study in reverse — additionally quizzes every card back → front as a separate schedule, without creating duplicate cards.

8 · Leeches & suspended cards

A card you keep forgetting isn't helping you — it's a leech. After 8 lapses a card is flagged and automatically suspended, and the collection page lists it under Suspended cards together with anything you suspended by hand. The usual fix: rewrite the card to be smaller or more concrete, then hit Resume to put it back in rotation.

9 · Analytics & the optimizer

The analytics page tracks every review: total reviews, day streak, success rate, an activity chart, a forecast of upcoming due load, and a per-session history.

Once you have 100+ reviews on record, the FSRS optimizer becomes available: it fits the scheduler's parameters to your own review history, so intervals reflect how you actually forget rather than the population average. Re-fit it now and then as your history grows.

11 · Profile, achievements & reminders

Milestones — streaks, review counts, cards mastered — unlock achievements automatically at the end of a session. In settings you can make your profile public, which gives you a page at /u/your-username showing your display name, bio, streak and achievements; private profiles share nothing. The same settings page has an opt-in for a daily email reminder when cards are waiting, and the delete-account button (which removes everything, permanently).