Retest review
A focused Linux CLI for inspecting regex matches, nested groups, ordering, and indexes.
Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
Retest is an open-source command-line regular expression tester for developers working in a Linux terminal. It accepts a regular expression and subject text, either through standard input or the --subject and -s options. Its output focuses on visual match inspection: complete matches are highlighted, nested groups and subgroups use different colors, and all non-crossing matches can be found. Match order and string indexes are also displayed, making it suited to quick command-line checks rather than broad regex workflow management.
The strongest part of Retest is its narrow inspection experience. Different colors for complete matches, nested groups, and subgroups help distinguish how a pattern is matching, while order and string indexes add useful positional context. The ability to accept input from standard input also fits terminal pipelines, and Linux binaries are provided through GitHub releases. Users who prefer compiling software can install it from source with Rust tooling. This combination suits developers who want a lightweight utility that fits existing command-line work.
Retest is less suitable when regex work requires explanations, replacement tools, debugging workflows, saved tests, or broader engine coverage. The published product information does not specify supported regex flavors, so users with engine-specific patterns should assess compatibility before adopting it. It is also limited to Linux, which narrows its fit for teams working across desktop platforms. Choose Retest for direct, minimal match inspection in a Linux terminal; choose another tester when interactive features, pattern guidance, persistence, or multi-platform access are central requirements.
Retest pros and cons
- Where it wins
- Highlights complete matches and nested groups with different colors
- Finds all non-crossing matches in supplied subject text
- Displays match order and string indexes in the terminal
- Where it doesn't
- Linux-only availability limits cross-platform use
- No documented regex flavor coverage
- No explanations, replacement, debugging, or saved tests
Retest fact sheet, pricing and score →
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