Kreuzberg

Kreuzberg Document Extraction

Kreuzberg is a high-performance document intelligence library with a Rust core and native bindings for Python, Node.js/TypeScript, Ruby, Go, Java, C#, PHP, and Elixir. It extracts text, tables, metadata, and images from 91+ file formats including PDF, Office documents, images (with OCR), HTML, email, archives, and academic formats.

Use this skill when writing code that:

• Extracts text or metadata from documents
• Performs OCR on scanned documents or images
• Batch-processes multiple files
• Configures extraction options (output format, chunking, OCR, language detection)
• Implements custom plugins (post-processors, validators, OCR backends)

Installation

Python

pip install kreuzberg
# Optional OCR backends:
pip install kreuzberg[easyocr]    # EasyOCR

Node.js

npm install @kreuzberg/node

Rust

# Cargo.toml
[dependencies]
kreuzberg = { version = "4", features = ["tokio-runtime"] }
# features: tokio-runtime (required for sync + batch), pdf, ocr, chunking,
#           embeddings, language-detection, keywords-yake, keywords-rake

CLI

# Download from GitHub releases, or:
cargo install kreuzberg-cli

Quick Start

Python (Async)

from kreuzberg import extract_file

result = await extract_file("document.pdf")
print(result.content)       # extracted text
print(result.metadata)      # document metadata
print(result.tables)        # extracted tables

Python (Sync)

from kreuzberg import extract_file_sync

result = extract_file_sync("document.pdf")
print(result.content)

Node.js

import { extractFile } from "@kreuzberg/node";

const result = await extractFile("document.pdf");
console.log(result.content);
console.log(result.metadata);
console.log(result.tables);

Node.js (Sync)

import { extractFileSync } from "@kreuzberg/node";

const result = extractFileSync("document.pdf");

Rust (Async)

use kreuzberg::{extract_file, ExtractionConfig};

#[tokio::main]
async fn main() -> kreuzberg::Result<()> {
    let config = ExtractionConfig::default();
    let result = extract_file("document.pdf", None, &config).await?;
    println!("{}", result.content);
    Ok(())
}

Rust (Sync) — requires tokio-runtime feature

use kreuzberg::{extract_file_sync, ExtractionConfig};

fn main() -> kreuzberg::Result<()> {
    let config = ExtractionConfig::default();
    let result = extract_file_sync("document.pdf", None, &config)?;
    println!("{}", result.content);
    Ok(())
}

CLI

kreuzberg extract document.pdf
kreuzberg extract document.pdf --format json
kreuzberg extract document.pdf --output-format markdown

Configuration

All languages use the same configuration structure with language-appropriate naming conventions.

Python (snake_case)

from kreuzberg import (
    ExtractionConfig, OcrConfig, TesseractConfig,
    PdfConfig, ChunkingConfig,
)

config = ExtractionConfig(
    ocr=OcrConfig(
        backend="tesseract",
        language="eng",
        tesseract_config=TesseractConfig(psm=6, enable_table_detection=True),
    ),
    pdf_options=PdfConfig(passwords=["secret123"]),
    chunking=ChunkingConfig(max_chars=1000, max_overlap=200),
    output_format="markdown",
)

result = await extract_file("document.pdf", config=config)

Node.js (camelCase)

import { extractFile, type ExtractionConfig } from "@kreuzberg/node";

const config: ExtractionConfig = {
  ocr: { backend: "tesseract", language: "eng" },
  pdfOptions: { passwords: ["secret123"] },
  chunking: { maxChars: 1000, maxOverlap: 200 },
  outputFormat: "markdown",
};

const result = await extractFile("document.pdf", null, config);

Rust (snake_case)

use kreuzberg::{ExtractionConfig, OcrConfig, ChunkingConfig, OutputFormat};

let config = ExtractionConfig {
    ocr: Some(OcrConfig {
        backend: "tesseract".into(),
        language: "eng".into(),
        ..Default::default()
    }),
    chunking: Some(ChunkingConfig {
        max_characters: 1000,
        overlap: 200,
        ..Default::default()
    }),
    output_format: OutputFormat::Markdown,
    ..Default::default()
};

let result = extract_file("document.pdf", None, &config).await?;

Config File (TOML)

output_format = "markdown"

[ocr]
backend = "tesseract"
language = "eng"

[chunking]
max_chars = 1000
max_overlap = 200

[pdf_options]
passwords = ["secret123"]

# CLI: auto-discovers kreuzberg.toml in current/parent directories
kreuzberg extract doc.pdf
# or explicit:
kreuzberg extract doc.pdf --config kreuzberg.toml
kreuzberg extract doc.pdf --config-json '{"ocr":{"backend":"tesseract","language":"deu"}}'

Batch Processing

Python

from kreuzberg import batch_extract_files, batch_extract_files_sync

# Async
results = await batch_extract_files(["doc1.pdf", "doc2.docx", "doc3.xlsx"])

# Sync
results = batch_extract_files_sync(["doc1.pdf", "doc2.docx"])

for result in results:
    print(f"{len(result.content)} chars extracted")

Node.js

import { batchExtractFiles } from "@kreuzberg/node";

const results = await batchExtractFiles(["doc1.pdf", "doc2.docx"]);

Rust — requires tokio-runtime feature

use kreuzberg::{batch_extract_file, ExtractionConfig};

let config = ExtractionConfig::default();
let paths = vec!["doc1.pdf", "doc2.docx"];
let results = batch_extract_file(paths, &config).await?;

CLI

kreuzberg batch *.pdf --format json
kreuzberg batch docs/*.docx --output-format markdown

OCR

OCR runs automatically for images and scanned PDFs. Tesseract is the default backend (native binding, no external install required).

Backends

• Tesseract (default): Built-in native binding. All Tesseract languages supported.
• EasyOCR (Python only): pip install kreuzberg[easyocr]. Pass easyocr_kwargs={"gpu": True}.
• PaddleOCR (Python only): Bundled since 4.8.5, no extra install needed. Pass paddleocr_kwargs={"use_angle_cls": True}.
• Guten (Node.js only): Built-in OCR backend via GutenOcrBackend.

Language Codes

config = ExtractionConfig(ocr=OcrConfig(language="eng"))       # English
config = ExtractionConfig(ocr=OcrConfig(language="eng+deu"))   # Multiple
config = ExtractionConfig(ocr=OcrConfig(language="all"))       # All installed

Force OCR

config = ExtractionConfig(force_ocr=True)  # OCR even if text is extractable

ExtractionResult Fields

Error Handling

Python

from kreuzberg import (
    extract_file_sync, KreuzbergError, ParsingError,
    OCRError, ValidationError, MissingDependencyError,
)

try:
    result = extract_file_sync("file.pdf")
except ParsingError as e:
    print(f"Failed to parse: {e}")
except OCRError as e:
    print(f"OCR failed: {e}")
except ValidationError as e:
    print(f"Invalid input: {e}")
except MissingDependencyError as e:
    print(f"Missing dependency: {e}")
except KreuzbergError as e:
    print(f"Extraction failed: {e}")

Node.js

import {
  extractFile,
  KreuzbergError,
  ParsingError,
  OcrError,
  ValidationError,
  MissingDependencyError,
} from "@kreuzberg/node";

try {
  const result = await extractFile("file.pdf");
} catch (e) {
  if (e instanceof ParsingError) {
    /* ... */
  } else if (e instanceof OcrError) {
    /* ... */
  } else if (e instanceof ValidationError) {
    /* ... */
  } else if (e instanceof KreuzbergError) {
    /* ... */
  }
}

Rust

use kreuzberg::{extract_file, ExtractionConfig, KreuzbergError};

let config = ExtractionConfig::default();
match extract_file("file.pdf", None, &config).await {
    Ok(result) => println!("{}", result.content),
    Err(KreuzbergError::Parsing(msg)) => eprintln!("Parse error: {msg}"),
    Err(KreuzbergError::Ocr(msg)) => eprintln!("OCR error: {msg}"),
    Err(e) => eprintln!("Error: {e}"),
}

Common Pitfalls

1. Python ChunkingConfig fields: Use max_chars and max_overlap, NOT max_characters or overlap.
2. Rust extract_file signature: Third argument is &ExtractionConfig (a reference), not Option. Use &ExtractionConfig::default() for defaults.
3. Rust feature gates: extract_file_sync, batch_extract_file, and batch_extract_file_sync all require features = ["tokio-runtime"] in Cargo.toml.
4. Rust async context: extract_file is async. Use #[tokio::main] or call from an async context.
5. CLI --format vs --output-format: --format controls CLI output (text/json). --output-format controls content format (plain/markdown/djot/html).
6. Node.js extractFile signature: extractFile(path, mimeType?, config?) — mimeType is the second arg (pass null to skip).
7. Python detect_mime_type: The function for detecting from bytes is detect_mime_type(data). For paths use detect_mime_type_from_path(path).
8. Config file field names: Use snake_case in TOML/YAML/JSON config files (e.g., max_chars, max_overlap, pdf_options).

Supported Formats (Summary)

See references/supported-formats.md for the complete format reference with MIME types.

Additional Resources

Detailed reference files for specific topics:

• Python API Reference — All functions, config classes, plugin protocols, exact signatures
• Node.js API Reference — All functions, TypeScript interfaces, worker pool APIs
• Rust API Reference — All functions with feature gates, structs, Cargo.toml examples
• CLI Reference — All commands, flags, config precedence, exit codes
• Configuration Reference — TOML/YAML/JSON formats, auto-discovery, env vars, full schema
• Supported Formats — All 85+ formats with file extensions and MIME types
• Advanced Features — Plugins, embeddings, MCP server, API server, security limits
• Other Language Bindings — Go, Ruby, Java, C#, PHP, Elixir, WASM, Docker

Full documentation: https://docs.kreuzberg.dev GitHub: https://github.com/kreuzberg-dev/kreuzberg