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Readability Analysis Tool (RAT)
Munich, Germany
What it is
Readability Analysis Tool (RAT) checks German text for readability anomalies using configurable rules. It accepts .docx files and creates a separate commented copy with a -rat.docx suffix, leaving the original document intact. RAT also produces an HTML report with text statistics, readability formulas, detected anomalies, and a quality gate indicating whether text may be too simple or difficult to understand. Its documented formulas are Flesch and Wiener Sachtextformel. Reports can include reading and speaking time, word and sentence counts, averages, common parts of speech, and configured keyword percentages. Rules and thresholds can be adjusted, and the report tracks anomalies users decline as false positives or incorporate. The tool runs from the command line using a Java JAR with configuration and output-directory options. The project lists performance of 40 seconds for 10,000 words, or 50 pages. RAT is free, available for Linux and Windows, and licensed under GPLv3.
For and against
For
- Free GPLv3 open-source project.
- Creates a commented copy while preserving the original.
- Generates an HTML report and quality gate.
- Rules and thresholds are configurable.
Against
- Documented rules support German.
- Input support is limited to .docx.
- Runs from the command line, not a hosted web interface.
The verdict
RAT offers configurable German readability checks, annotated document copies, and detailed reports at no cost. Its documented language, file type, and command-line workflow are important constraints to consider.
Who it suits
RAT suits readers and editors working with German .docx text who can use a command-line tool. Its reports and configurable rules may help assess readability and review flagged passages.
Plans and prices
Readability Analysis Tool (RAT)
GPLv3 open-source project · supports .docx · German readability rules
Read 7 Oct 2026 · github.com
On the record
- Annotations
- RAT annotates detected anomalies as comments in a .docx copy with a -rat.docx suffix, preserving the original document.github.com · read 7 Oct 2026
- Configurable rules
- Anomaly rules and thresholds can be configured, and the report records anomalies users declined as false positives or incorporated.github.com · read 7 Oct 2026
- Document support
- The documented supported file type is .docx.github.com · read 7 Oct 2026
- Execution
- RAT is invoked from the command line with a Java JAR and accepts configuration and output-directory options.github.com · read 7 Oct 2026
- Language
- The documented readability rules support German.github.com · read 7 Oct 2026
- License
- The project lists its license as GPLv3.github.com · read 7 Oct 2026
- Notable limits
- The project documentation lists German rules and .docx input, and describes command-line execution rather than a hosted web interface.github.com · read 7 Oct 2026
- Performance
- The project lists performance as 40 seconds for 10,000 words, or 50 pages.github.com · read 7 Oct 2026
- Purpose
- RAT detects readability anomalies in text based on readability rules, similar to bug patterns in static code analysis.github.com · read 7 Oct 2026
- Quality gate
- The quality gate aggregates formulas, statistics, and anomalies to indicate whether text is too trivial or too hard to understand.github.com · read 7 Oct 2026
- Readability formulas
- The documented formulas are Flesch and Wiener Sachtextformel.github.com · read 7 Oct 2026
- Reports
- RAT creates an HTML report with text statistics, readability formulas, anomalies, and a quality gate.github.com · read 7 Oct 2026
- Statistics
- The report includes reading and speaking time, sentence and word counts, average word and sentence measures, common parts of speech, and configured keyword percentages.github.com · read 7 Oct 2026
- Technology
- The listed technologies are Java, UIMA, and DKPro Core.github.com · read 7 Oct 2026
