Code Duplication Detector

Paste code and find repeated 4+ line blocks and the percentage of duplicated lines - a single-file preview of what repo-wide duplication analysis catches.

Paste code (one file)

75.0%

Duplicated lines

Duplicate blocks (4+ lines)

Repeated at lines 4, 17

if (!res.ok) {
throw new Error("Request failed: " + res.status);
}
return await res.json();

Repeated at lines 5, 18

throw new Error("Request failed: " + res.status);
}
return await res.json();
} catch (err) {

Repeated at lines 6, 19

}
return await res.json();
} catch (err) {
console.error("Failed to fetch:", err);

Repeated at lines 7, 20

return await res.json();
} catch (err) {
console.error("Failed to fetch:", err);
return null;

Repeated at lines 8, 21

} catch (err) {
console.error("Failed to fetch:", err);
return null;
}

Exact-match block detection - catches literal copy-paste, not renamed-variable clones. The full Repository Analysis engine goes deeper across your whole codebase.

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