Regex Vis
View a regular expression's branches, groups, and repetition as a diagram, then check it against test strings.
What does Regex Vis do?
Regex Vis turns a regular expression into connected nodes and checks strings in its Test tab. The diagram sits beside the pattern, making branches, groups, and repetition easier to compare.
The official project lists visualization, visual editing, and matching tests. We tested pattern input, diagram generation, and string matching, but did not use visual editing.
Why it is useful
A visible branch is easier to point out when explaining a pattern than a sequence of brackets and symbols. Follow the diagram with matching and non-matching examples before putting the rule into code.
Good fit for
Developers reading, explaining, or checking regular expressions, and learners working with groups, alternatives, and quantifiers.
Try it when
We entered ^a(b|c)+d$ and pressed Enter. The diagram showed the start, a, Group #1 with separate b and c branches, one-or-more repetition, d, and the end.
In Test, with all flags unchecked, abbd and acbd each produced a green check. ad and xacbd each produced a red cross. These examples check that the middle branch can repeat but cannot be omitted, and that an extra leading character is rejected.
Before using it
Our pattern appeared in the URL’s r query parameter. Inspect a URL before sharing it, and do not include credentials, personal data, or internal information. Test the pattern again in your target runtime. We did not test visual editing, flag changes, Unicode, complex-pattern performance, or compatibility with other engines.
