# Plagiarism Detection Levels

> The three levels of plagiarism matching in Copyleaks, Identical Matches, Minor Changes, and Paraphrased Content, plus cross-language detection.

The Copyleaks plagiarism API matches content at three levels: Identical Matches, Minor Changes, and Paraphrased Content (Related Meaning). Each can be enabled or disabled per scan to tune accuracy and noise.

## Introduction

Copyleaks matches content beyond simple word-for-word comparison. The three levels together cover everything from exact duplication to paraphrasing and cross-language translation.

Each detection level serves a specific purpose and can be enabled or disabled according to your specific needs:

1. **Identical Matches**: Exact word-for-word matches
2. **Minor Changes**: Content with slight variations
3. **Paraphrased Content**: Rewritten text that conveys the same meaning

## Detection Levels Explained

### Identical Matches

Identical matches represent the most straightforward type of content matching, focusing on exact, word-for-word duplication.

- **Description**: Detects content that has been copied verbatim from another source without any alterations.
- **Use Case**: Ideal for finding direct plagiarism where content has been copied and pasted without modification.
- **Configuration**: Set `properties.filters.identicalEnabled` to `true` (enabled by default).
- **Example**:
  - **Original**: "The quick brown fox jumps over the lazy dog."
  - **Matched**: "The quick brown fox jumps over the lazy dog."

<Tip>
  For cases where you only want to detect identical matches, you can disable the other detection levels. See our [Identical Matches Detection](/concepts/features/identical-matches) guide for details.
</Tip>

### Minor Changes

The minor changes detection level identifies content that has been slightly modified but remains fundamentally the same as the original source.

- **Description**: Detects content where small changes have been made, such as altering word forms, switching tenses, or making minimal substitutions.
- **Use Case**: Helpful for identifying cases where someone has made superficial changes to disguise copied content.
- **Configuration**: Set `properties.filters.minorChangesEnabled` to `true` (enabled by default).
- **Examples**:
  - **Original**: "The quick brown fox jumps over the lazy dog."
  - **Matched**: "A quick brown fox jumps over the lazy dog."

### Paraphrased Content (Related Meaning)

The paraphrased content detection level identifies substantial rewrites that maintain the same core meaning as the original source.

- **Description**: Detects content that has been significantly rewritten while preserving the original meaning or ideas.
- **Use Case**: Essential for identifying sophisticated plagiarism where content has been carefully reworded to avoid detection.
- **Configuration**: Set `properties.filters.relatedMeaningEnabled` to `true` (enabled by default).
- **Examples**:
  - **Original**: "The quick brown fox jumps over the lazy dog."
  - **Matched**: "That speedy brown fox just jumped right over a sleeping dog" (same meaning, different words)

<Note>
  The paraphrased content detection uses advanced natural language processing to understand semantic meaning beyond simple word matching.
</Note>

### Cross-Language Detection

A particularly powerful feature of Copyleaks' paraphrased content detection is its ability to identify content that has been translated from one language to another.

- **Description**: Detects content that has been translated from the original source into a different language.
- **Use Case**: Critical for organizations working in multilingual environments or checking content across language boundaries.
- **Configuration**: Configure through the `properties.scanning.crossLanguages` property.
- **Example**:
  - **Original (English)**: "The quick brown fox jumps over the lazy dog."
  - **Matched (Spanish)**: "El rápido zorro marrón salta sobre el perro perezoso."
  - **Matched (French)**: "Le renard brun rapide saute par-dessus le chien paresseux."

<Warning>
  Cross-language detection requires additional processing and may consume additional credits. Only languages listed in the [supported cross-languages](/reference/actions/miscellaneous/supported-cross-languages) documentation can be used.
</Warning>

## Configuration

All three detection levels are enabled by default. You can customize which levels to include in your scan by modifying the `properties.filters` object in your API request:

```json title="Detection Levels Configuration"
{
  "properties": {
    "filters": {
      "identicalEnabled": true,      // Enable/disable identical matches
      "minorChangesEnabled": true,   // Enable/disable minor changes detection
      "relatedMeaningEnabled": true  // Enable/disable paraphrased content detection
    }
  }
}
```

### Recommended Configurations

Depending on your use case, you might want to adjust which detection levels are enabled:

#### High Precision (Fewer False Positives)
```json
{
  "properties": {
    "filters": {
      "identicalEnabled": true,
      "minorChangesEnabled": true,
      "relatedMeaningEnabled": false
    }
  }
}
```

#### High Recall (Catch All Potential Matches)
```json
{
  "properties": {
    "filters": {
      "identicalEnabled": true,
      "minorChangesEnabled": true,
      "relatedMeaningEnabled": true
    }
  }
}
```

#### Identical Only (Exact Matches Only)
```json
{
  "properties": {
    "filters": {
      "identicalEnabled": true,
      "minorChangesEnabled": false,
      "relatedMeaningEnabled": false
    }
  }
}
```

## Next Steps

After understanding the different detection levels:

<CardGroup cols={2}>
  <Card title="Configure Identical Matches" icon="equals" href="/concepts/features/identical-matches" />
  <Card title="Detect Plagiarism in Text" icon="magnifying-glass" href="/guides/authenticity/detect-plagiarism-text" />
  <Card title="Detect AI-Generated Content" icon="robot" href="/guides/authenticity/detect-ai-generated-content" />
  <Card title="Cross-Language Detection" icon="language" href="/reference/actions/miscellaneous/supported-cross-languages" />
</CardGroup>

## Support

If you need assistance with configuring detection levels or have questions about which settings are best for your use case, please [contact our support team](mailto:support@copyleaks.com).