CloneWorks
CloneWorks prepares source code into fragments and detects clones in those fragments.
What CloneWorks is
CloneWorks prepares source code into fragments and detects clones in those fragments. Its input builder accepts Java, C, C++, C#, and Python, and can extract code at block, function, or file granularity. The detector uses a token-based method and accepts a minimum similarity threshold from 0.0 to 1.0; the repository describes a test run with Type-3 clone detection. For an index larger than available memory, CloneWorks offers a partitioned partial-index mode, though the partition size must be established experimentally. It runs on Linux, macOS, and Windows and requires FreeTXL 10.6 or later, gcc, make, and Java 7 or later. The input builder is slower on Cygwin because process creation is slower on Windows. CloneWorks is free, but its license requires acknowledgement and says copies, modifications, and derivatives must stay under the license and be distributed without charge. The license provides the software as-is without warranty. The maintainer invites questions and bug reports by email and says he is happy to assist with using CloneWorks.
Good
- Supports Java, C, C++, C#, and Python input.
- Extracts blocks, functions, or files.
- Accepts similarity thresholds from 0.0 to 1.0.
- Offers a partitioned mode for indexes exceeding memory.
- Free to use under its license terms.
Watch out
- Requires FreeTXL, gcc, make, and Java 7 or later.
- Cygwin input building is slower on Windows.
- Partition size must be determined experimentally.
- License requires redistribution and derivatives to remain free.
Who it suits
CloneWorks may suit developers or researchers who need to prepare source code and detect clones across the listed programming languages. It requires several installed development tools and runtimes.
Verdict
CloneWorks offers configurable extraction and token-based clone detection across five listed languages. Check its system requirements and free-redistribution conditions before adopting or sharing modified versions.
Plans and prices
From CloneWorks's own pricing page, checked 3 Oct 2026.
| Plan | Price | What it gives you |
|---|---|---|
| CloneWorks | Free | Use requires acknowledgement; no charge may be made · Redistribution and derivatives must use this license and be free of charge |
The facts
Each one read from CloneWorks's own pages, with the date it was checked.
What it does
- Clone types
- The repository describes a test run that performs Type-3 clone detection.checked 3 Oct 2026
- Granularity
- The input builder supports block, function, and file granularity for code extraction.checked 3 Oct 2026
- Languages
- The input builder lists Java, C, C++, C#, and Python as supported input languages.checked 3 Oct 2026
- Large inputs
- A partitioned partial-index mode is available when the index exceeds available memory, and the README says its partition size must be determined experimentally.checked 3 Oct 2026
- License terms
- The license permits copying, modification, and redistribution of CloneWorks and derivatives if they remain under the license and are distributed without charge.checked 3 Oct 2026
- Purpose
- CloneWorks prepares source code and detects code clones in the prepared fragments.checked 3 Oct 2026
- Similarity threshold
- The clone detector accepts a minimum similarity threshold from 0.0 to 1.0.checked 3 Oct 2026
- Support
- Jeffrey Svajlenko invites questions and bug reports by email and says he is happy to assist with using CloneWorks.checked 3 Oct 2026
- System requirements
- CloneWorks requires FreeTXL 10.6 or later, gcc, make, and Java 7 or later.checked 3 Oct 2026
- Warranty
- The license provides CloneWorks as-is without warranty, including implied warranties of merchantability or fitness for a particular purpose.checked 3 Oct 2026
Where it runs
- Platforms
- The README says CloneWorks can be used on Linux and other Unix-like systems, was tested on Ubuntu and OS X, and should work on Cygwin.checked 3 Oct 2026
- Windows limitation
- The README says the input builder is slower on Cygwin because process creation is slower on Windows.checked 3 Oct 2026
The full review of CloneWorks
CloneWorks is a self-hosted repository scanner for developers and researchers who need configurable source extraction and token-based clone analysis. It suits technically equipped users working in its supported languages; teams seeking a packaged service or commercial redistribution should look elsewhere.
Overview
CloneWorks prepares source code into fragments and detects similarities across a repository. Its token-based method is aimed at code duplication, and a documented test run performs Type-3 clone detection, making it relevant when copied code has been changed rather than left identical. The tool runs on Linux, macOS, and Windows and can be operated as a self-hosted installation.
The input builder accepts Java, C, C++, C#, and Python. Extraction can be set to block, function, or file granularity, so a review can focus on small sections, complete routines, or whole files. That control is valuable when a team wants to distinguish local repetition from larger duplicated components, although projects written in other languages are outside the stated input support.
Key features
Similarity tuning
The detector accepts a minimum similarity threshold from 0.0 to 1.0. A lower setting can expose more loosely related fragments, while a higher setting narrows results toward closer matches. This range gives experienced users meaningful control, but selecting a useful value requires an understanding of the repository and the duplication patterns under review.
Processing large indexes
Partitioned partial-index mode is available when an index exceeds available memory. It provides a path for repositories that do not fit into a single in-memory index. The README says the partition size must be determined experimentally, so handling a large codebase involves operational tuning rather than a fixed, documented setting.
Windows workflow
CloneWorks supports Windows, but its input builder is slower on Cygwin because process creation is slower on Windows. That makes the platform viable while giving Linux or macOS an advantage for users who regularly rebuild inputs.
Pricing
CloneWorks: free. There is no charge, but use requires acknowledgement. No charge may be made, and redistribution or derivatives must remain under the same license and be free of charge. Those terms suit personal work, academic use, and organizations able to distribute their tooling at no cost; they rule out packaging CloneWorks or modified versions as a paid product.
Installation also carries a technical cost. CloneWorks requires FreeTXL 10.6 or later, gcc, make, and Java 7 or later. Teams without those dependencies or the expertise to maintain a self-hosted build may spend more effort getting started than with a packaged analyzer.
Platforms
CloneWorks runs on Linux, macOS, and Windows. It is self-hosted rather than a hosted scanning service. Windows users should account for the slower Cygwin input-builder process, while all platforms require the listed FreeTXL, compiler, build, and Java dependencies.
Who it's for
CloneWorks is a strong fit for developers, maintainers, and researchers who need repository-wide clone analysis in Java, C, C++, C#, or Python and want to choose extraction granularity and similarity thresholds themselves. It is also appropriate when a partitioned index is necessary for a memory-constrained environment and the team can tune partition size experimentally.
It is a weaker choice for teams using unsupported languages, users who want a turnkey hosted workflow, or organizations that need to sell a product containing the detector. The as-is license provides no warranty, including implied warranties of merchantability or fitness for a particular purpose, so production adoption should include the user's own risk assessment. Jeffrey Svajlenko invites questions and bug reports by email and offers assistance with using CloneWorks.
Pros and cons
Pros
- Granularity control: block, function, and file extraction supports different duplication-review objectives.
- Adjustable matching: a 0.0–1.0 minimum similarity threshold lets experienced users tune result breadth.
- Type-3 capability: the documented test run addresses modified as well as identical-looking code.
- Three desktop platforms: Linux, macOS, and Windows support broad self-hosted deployment.
- Free use: the software has no purchase price.
Cons
- Dependency-heavy setup: FreeTXL 10.6 or later, gcc, make, and Java 7 or later are required.
- Limited language coverage: the input builder supports five named languages, excluding projects outside that set.
- Large-index tuning: partition size must be established experimentally.
- Windows slowdown: Cygwin input building is slower because of process-creation overhead.
- Redistribution restrictions: derivatives must remain free and under the license, preventing paid distribution.
- No warranty: the license supplies the software as-is without implied fitness or merchantability protection.
Alternatives
Browse Code Clone Detection Tools for a wider category comparison.
- Duplo is a free Linux, macOS, and Windows option with prebuilt binaries for Alpine Linux, macOS, and Windows under GNU GPL v2 or later; choose it when packaged binaries matter more than CloneWorks' extraction controls.
- PMD is a free downloadable static code analyzer for Linux, macOS, Windows, and self-hosted use under a BSD-style license; choose it when broader static analysis is the priority.
- Simian Similarity Analyzer is free, open source, and Apache License 2.0 across Linux, macOS, and Windows; choose it when that licensing model and platform coverage fit better.
- dcd is free on Linux and macOS under AGPL-3.0, with optional priority support; choose it when those platforms and licensing terms suit your deployment.
- jscpd is a free option spanning API, Linux, macOS, self-hosted, and Windows environments; choose it when that deployment range is more useful.
- NiCad is free and open source under MIT, supports Linux, macOS, self-hosted, and Windows, and requires OpenTxl 11 or later; choose it when MIT licensing or its platform set is preferable.
- CCFinderSW is free, MIT-licensed Windows software requiring Java Runtime Environment 8 or later; choose it for a Windows-only MIT-licensed alternative.
- Algo VPN is a free self-hosted VPN setup project, not a code-clone detector.
Verdict
Choose CloneWorks if you need self-hosted, repository-wide clone detection with selectable extraction levels and a tunable similarity threshold across its five supported languages. Look elsewhere if you need a simpler dependency profile, support for other languages, hosted operation, or permission to redistribute a modified commercial product.
