Create ASCII from Regex

How to use Create ASCII from Regex

1. 1. Paste your regex pattern. Paste a regular expression like [a-c]{3} into the input pane describing the strings you want generated, including any character classes or repetition counts.
2. 2. Set How many strings. Enter the number of random matching strings to generate; more strings give you a broader sample of what the pattern allows.
3. 3. Copy the generated strings. Copy the list of randomly generated strings, each one guaranteed to match your original pattern, and drop them into your test suite or sample data.

When to use Create ASCII from Regex

Create ASCII from Regex runs a regular expression backwards, generating random strings that match a given pattern instead of matching a pattern against existing text. It is useful whenever you need realistic sample data that must satisfy a specific format like a fixed character class or length.

• Generating test fixtures for a validation regex. You wrote a regex to validate usernames or product codes and need sample valid inputs for your unit tests. Generating several matching strings here gives you ready made fixtures without inventing them by hand.
• Producing sample data for a form field. A form field enforces a pattern like three letters followed by four digits and you need example values for a demo or design mockup. Generating matches here produces believable looking sample data instantly.
• Fuzzing a parser with valid inputs. You're testing a parser or state machine and want a batch of inputs that are guaranteed valid according to its grammar. Generating many matches for the pattern gives you varied valid test cases quickly.
• Checking that a regex isn't too restrictive. You suspect a regex is more restrictive than intended and want to see the range of strings it actually allows. Generating several examples shows the real space of matching strings.

Examples

[a-c]{3}

bac
cab
aba

About the Create ASCII from Regex tool

Frequently asked questions