Online memory trainer

Digits Backward: type the number in reverse

Also known as: backward digit span, reverse digit span test, digits in reverse order

A number appears for a second. Remember it and type the digits starting from the end: 472 becomes 274. Five correct answers in a row make the number longer, three mistakes in a row make it shorter. A game lasts two minutes, and you can play 10 minutes a day without signing up.

Go to the game ↓

2 minutesper game
3–8 digitslength grows as you succeed
No sign-up10 minutes a day
Progress30-day chart

What it trains

What reversing digits trains

Remembering a number and repeating it is a short-term memory task. Repeating it backward is harder: you have to hold the digits and rearrange them in your head at the same time. That’s working memory at work.

Your score is the number of correct answers in two minutes; each mistake costs a point. The results also show the longest number you managed. Once you sign up, your games are saved and you can see a chart in your account.

Remember the Number feels easyYou want the same task, only harder
You mix up digits when copyingYou remember the number, but the order drifts
You lose track when things need reorderingYou can remember it, but flipping it is another story
You want a quick workoutTwo minutes, just digits and buttons

Working memory

Hold the digits and rearrange them in reverse order.

Short-term memory

The number shows for only about a second.

Attention to order

It’s not just the digits that matter, but their positions.

Accuracy

A mistake costs a point, so rushing without checking doesn’t pay.

Rules

How to play

Start
Press “Start”. The first three-digit number appears right away, and a two-minute timer begins.
Remember
The number shows for about a second, then the boxes clear.
Type it backward
Type the digits from last to first with the on-screen buttons or your keyboard. Backspace deletes the last digit.
Check
Your answer is checked as soon as all digits are in. If you make a mistake, we show the number and how it looks reversed.
Length
Five correct in a row: one digit more, up to eight. Three mistakes in a row: one digit less, but never below three.

Play online

Digits Backward online

Press “Start”, memorize the number and type it in reverse.

Digits Backward

A number flashes for a second. Type it backward: 472 becomes 274. Five right in a row and the number gets longer; three mistakes in a row and it gets shorter.

Free play left today without signing up: 10 min

Method

What the exercise is based on

Repeating digits forward and backward is a long-standing task in psychological memory tests, such as the Wechsler scales. Forward repetition shows your short-term memory span, while backward repetition also requires rearranging the digits in your mind.

The forward version on our site is Remember the Number. A similar task with positions on a board instead of digits is Backward Corsi Blocks.

3Start with three digitsShorter than in Remember the Number: flipping a number is harder.

+1Five correct in a rowThe number gets one digit longer, up to eight.

−1Three mistakes in a rowThe number gets shorter, but never below three digits.

Who it’s for

Which ages

Adults

A short, intense memory warm-up: two minutes, no preparation.

Kids

Not part of the “Kids” collection. School-age kids who handle Remember the Number with ease can give it a try: the game starts with three digits.

60+

Not part of the “60+” collection. If you’d like a step up from Remember the Number, give it a try: the number gets shorter when you make mistakes.

Questions

Frequently asked questions

Do I start with the first digit or the last one?

With the last one. If you see 5 8 1, type 1 8 5. A hint above the boxes reminds you to type the number backward.

How is it different from Remember the Number?

There you type the number in the same order, starting with four digits. Here you have to reverse it, so you start with three.

How long is the number shown?

About a second. Slightly longer for seven-digit numbers and slightly shorter for eight-digit ones.

Can I use the keyboard?

Yes. You can type digits on your computer keyboard; Backspace deletes the last digit. On a phone there are on-screen buttons.

Do I need to sign up?

No, you can play 10 minutes a day right away. A free account lets you keep playing, save your results, track your progress and unlock the daily workout.

Save your results and track your progress

Free sign-up: round history, a chart by skill and a daily workout of 5 exercises. No credit card needed.

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Digits Backward: type the number in reverse