Error checking test practice: original against copy, on the clock

An error checking test looks easy. Your eyes agree with the copy while a swapped pair of digits slips past. Employers use it to see how many slips you catch in the time allowed.

Try one: count how many fields in the copy differ from the original. Capitals and spaces count.

What is an error checking test?

An error checking test, sometimes called an attention to detail test, asks how accurately you compare information against a clock. You see an original and a copy, such as codes, dates, amounts or phone numbers, and decide where the copy has gone wrong. If you're applying for an admin, data entry, sales support or purchasing role, you may meet one.

Your test may ask you to pick the exact match or mark each row instead of counting.

Which mistakes hide in the copy on an error checking test?

• Swapped neighbours. Two characters change places.
• Replaced. A 5 becomes S, an 8 becomes B, a 2 becomes Z, a 6 becomes G, or the other way round.
• A missing or extra character. A digit drops out of a phone number, or a letter doubles in a code.
• Case and spacing. A capital turns lower case, or a space appears where there was none.

And sometimes the copy is perfect. If you expect a mistake in every row, you start seeing ones that are not there.

How do you spot differences faster on an error checking test?

1. Read in chunks. Compare three or four characters at a time. A swapped pair in the middle of a code is invisible to a whole-word read.
2. Check the length first. A copy that is one character longer or shorter is wrong before you read a single digit.
3. Give each kind of field its own check. Say a date as day, month, year. Read an amount by sign, comma and point. Split a phone number in two.
4. Move on once a field matches.

Do you have to finish an error checking test?

Often, no. Many timed tests give you more questions than most people can answer in the time. Find a pace at which you still compare every character.

How should you practise for an error checking test?

Practise in short timed sessions, because the skill is keeping your attention sharp against a clock, not knowing more. Note which kind keeps getting past you: swapped neighbours, replaced characters, a missing or extra character, or case and spacing.

If your assessment also has a numbers or a shapes section, try our numerical reasoning practice and logical reasoning practice. To see how we build and check our questions, read our methodology.