A ten-question regex quiz you answer by writing real patterns that run against test strings, one 15-minute clock, and a score broken down by skill area. No sign-up to start.
Working knowledge
| Skill area | Score | Share correct |
|---|---|---|
| Basics | 2/2 | |
| Groups and alternation | 2/2 | |
| Real-world validation | 1/2 | |
| Extraction and cleanup | 1/2 | |
| Advanced | 1/2 |
Regular expressions come down to a short list of skills, from character classes to lookarounds. The test takes two questions from each of the five levels, picked at random each time.
Literal text, character classes and ranges, counted repeats, anchors, escaping and the i flag. [a-z] \d + * ? ^ $
2 of 1015 exercisesAlternatives, capturing and non-capturing groups, optional and repeated groups, and backreferences. (...) (?:...) | \1
2 of 1015 exercisesWhole-line patterns for the formats that come up at work: dates, times, email addresses, URLs, IP addresses and money. ranges built from alternation
2 of 1020 exercisesPulling fields out of log lines, URLs and CSV rows, and search and replace: trimming, reformatting dates, stripping tags. captures $1 the g flag
2 of 1018 exercisesLookahead and lookbehind, lazy matching, named groups, and the m, s and u flags. (?=...) (?<!...) .*? (?<name>...)
2 of 1020 exercisesThese come from the same pool as the test, one of each kind: match, extract and replace. In the test you type the pattern, the lines shown highlight as you type, and your answer is also checked on hidden test strings.
The whole line must match. Match a five-digit ZIP code, optionally followed by a hyphen and four more digits.
Test lines9 lines shown, plus 4 hidden test strings in the exercise
| Line | Should match |
|---|---|
| 90210 | yes |
| 1234 | no |
| 02134 | yes |
| 123456 | no |
| 12345-6789 | yes |
| 12345-678 | no |
| 00501 | yes |
| 12345 6789 | no |
| ABCDE | no |
Pattern/\d{5}(?:-\d{4})?/
\d{5}(?:-\d{4})? allows 90210 and 12345-6789 but nothing in between.
Capture the first standalone four-digit number on each line in group 1. Digits that are part of a longer number do not count. Lines without one give no match.
Lines to extract from4 lines shown, plus 3 hidden test strings in the exercise
| Line | Expected capture |
|---|---|
| Released in 1998 | "1998" |
| Copyright 2024 Acme | "2024" |
| Founded 1887, rebuilt 1920 | "1887" |
| No year here | no match |
Pattern/\b(\d{4})\b/
\b(\d{4})\b captures four digits with a boundary on each side, so 12345 is skipped instead of yielding 1234.
Rewrite every date written MM/DD/YYYY as YYYY-MM-DD. Leave everything else unchanged.
Lines to rewrite3 lines shown, plus 2 hidden test strings in the exercise
| Line | Expected output |
|---|---|
| Due 04/15/2025 | Due 2025-04-15 |
| 12/31/1999 and 01/01/2000 | 1999-12-31 and 2000-01-01 |
| no date | no date |
Pattern/(\d{2})/(\d{2})/(\d{4})/g
Replace with$3-$1-$2
(\d{2})/(\d{2})/(\d{4}) with the replacement $3-$1-$2 and the g flag reorders every date on the line.
Start with the first levels and work up. Short daily practice moves this score quickly.
The core is there. The areas you missed are the ones to drill next.
You solved questions from nearly every level under the clock. Drill the one or two areas you missed and you are in good shape.
These bands describe this test only. They are not a pass mark for any employer or course.
10 questions from 5 skill areas, 15 minutes on the clock. It starts right here, with no account and no email.
Six slips worth fixing before a timed regex test.
Yes. The test and every exercise on Regexdrill are free. There is no card, no daily limit and nothing to unlock.
No to both. The test starts in one click and runs in your browser. The lines shown highlight as you type, and your answer is checked on the server against hidden test strings.
Up to 15 minutes. There are 10 questions on one clock, and the test ends when you finish the last question or the time runs out.
One point per question, 10 in total. A pattern scores when it passes every line shown and every hidden test string. Skipped or unsolved questions count as wrong. You also get a breakdown by skill area.
No. Every question is hands-on: you type a pattern, and for replace questions the replacement text, and it is run against real test strings. That is closer to how regular expressions are used at work than picking an answer from a list.
The JavaScript flavor, with the flags g, i, m, s and u. Character classes, groups, backreferences, lookahead, lookbehind and named groups work as they do in current browsers. Most of what you practice carries over to Python, Java and PCRE with small differences.
Yes, as often as you like. The questions are drawn at random from the exercise pool, so a retake is a different test.
Your result links straight to the exercises for the areas you missed. All 88 exercises are free, each with hidden test strings and a reference answer. Certificates come with the Dravari bundle.
Ten questions, 15 minutes, a score by skill area. Free, and no sign-up to start.
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