Docling Document Parser
Docling is a document parsing library that converts PDFs, Word documents, PowerPoint, images, and other formats into structured data with advanced layout understanding.
Quick Start
Basic document conversion:
from docling.document_converter import DocumentConverter
source = "https://arxiv.org/pdf/2408.09869" # URL, Path, or BytesIO converter = DocumentConverter() result = converter.convert(source) print(result.document.export_to_markdown())
Core Concepts
DocumentConverter
The main entry point for document conversion. Supports various input formats and conversion options.
from docling.document_converter import DocumentConverter from docling.datamodel.base_models import InputFormat from docling.document_converter import PdfFormatOption from docling.datamodel.pipeline_options import PdfPipelineOptions
Basic converter (all formats enabled)
converter = DocumentConverter()
Restricted formats
converter = DocumentConverter( allowed_formats=[InputFormat.PDF, InputFormat.DOCX] )
Custom pipeline options
pipeline_options = PdfPipelineOptions() pipeline_options.do_ocr = True pipeline_options.do_table_structure = True
converter = DocumentConverter( format_options={ InputFormat.PDF: PdfFormatOption(pipeline_options=pipeline_options) } )
ConversionResult
All conversion operations return a ConversionResult containing:
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document : The parsed DoclingDocument
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status : ConversionStatus.SUCCESS , PARTIAL_SUCCESS , or FAILURE
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errors : List of errors encountered during conversion
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input : Information about the source document
result = converter.convert("document.pdf")
if result.status == ConversionStatus.SUCCESS: markdown = result.document.export_to_markdown() html = result.document.export_to_html() data = result.document.export_to_dict()
Supported Formats
Input Formats
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Documents: PDF, DOCX, PPTX, XLSX
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Markup: HTML, Markdown, AsciiDoc
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Data: CSV, JSON (Docling format)
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Images: PNG, JPEG, TIFF, BMP, WEBP
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Audio: WAV, MP3
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Video Text: WebVTT
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Schema-specific: USPTO XML, JATS XML, METS-GBS
Output Formats
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Markdown: export_to_markdown() or save_as_markdown()
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HTML: export_to_html() or save_as_html()
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JSON: export_to_dict() or save_as_json() (note: no export_to_json() method)
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Text: export_to_text() or export_to_markdown(strict_text=True) or save_as_markdown(strict_text=True)
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DocTags: export_to_doctags() or save_as_doctags()
Common Patterns
Single File Conversion
from docling.document_converter import DocumentConverter
converter = DocumentConverter() result = converter.convert("document.pdf")
Export to different formats
markdown = result.document.export_to_markdown() html = result.document.export_to_html() json_data = result.document.export_to_dict()
Or save directly to file
result.document.save_as_markdown("output.md") result.document.save_as_html("output.html") result.document.save_as_json("output.json")
Batch Processing
See references/batch.md for details on convert_all() .
URL Conversion
converter = DocumentConverter() result = converter.convert("https://example.com/document.pdf")
Binary Stream Conversion
from io import BytesIO from docling.datamodel.base_models import DocumentStream
with open("document.pdf", "rb") as f: buf = BytesIO(f.read())
source = DocumentStream(name="document.pdf", stream=buf) result = converter.convert(source)
Format-Specific Options
from docling.datamodel.base_models import InputFormat from docling.datamodel.pipeline_options import PdfPipelineOptions from docling.document_converter import DocumentConverter, PdfFormatOption
Configure PDF-specific options
pipeline_options = PdfPipelineOptions() pipeline_options.do_ocr = True pipeline_options.ocr_options.lang = ["en", "es"] pipeline_options.do_table_structure = True pipeline_options.generate_page_images = True
converter = DocumentConverter( format_options={ InputFormat.PDF: PdfFormatOption(pipeline_options=pipeline_options) } )
Resource Limits
converter = DocumentConverter()
Limit file size (bytes) and page count
result = converter.convert( "large_document.pdf", max_file_size=20_971_520, # 20 MB max_num_pages=100 )
Document Chunking
See references/chunking.md for RAG integration.
DoclingDocument Structure
The DoclingDocument is a Pydantic model representing parsed content:
Access document structure
doc = result.document
Content items (lists)
doc.texts # TextItem instances (paragraphs, headings, etc.) doc.tables # TableItem instances doc.pictures # PictureItem instances doc.key_value_items # Key-value pairs
Structure (tree nodes)
doc.body # Main content hierarchy doc.furniture # Headers, footers, page numbers doc.groups # Lists, chapters, sections
Iterate all elements in reading order
for item, level in doc.iterate_items(): print(f"{' ' * level}{item.label}: {item.text[:50]}")
Advanced Features
OCR Configuration
from docling.datamodel.pipeline_options import ( PdfPipelineOptions, EasyOcrOptions, TesseractOcrOptions, TesseractCliOcrOptions, OcrMacOptions, RapidOcrOptions )
EasyOCR (default)
pipeline_options = PdfPipelineOptions() pipeline_options.do_ocr = True pipeline_options.ocr_options = EasyOcrOptions(lang=["en", "de"])
Tesseract
pipeline_options = PdfPipelineOptions() pipeline_options.do_ocr = True pipeline_options.ocr_options = TesseractOcrOptions(lang=["eng", "deu"])
RapidOCR
pipeline_options = PdfPipelineOptions() pipeline_options.do_ocr = True pipeline_options.ocr_options = RapidOcrOptions()
Table Extraction Options
from docling.datamodel.pipeline_options import ( PdfPipelineOptions, TableFormerMode )
pipeline_options = PdfPipelineOptions() pipeline_options.do_table_structure = True
Use cell matching (map to PDF cells)
pipeline_options.table_structure_options.do_cell_matching = True
Or use predicted cells
pipeline_options.table_structure_options.do_cell_matching = False
Choose accuracy mode
pipeline_options.table_structure_options.mode = TableFormerMode.ACCURATE
Page Images
pipeline_options = PdfPipelineOptions() pipeline_options.generate_page_images = True # Needed for HTML export with images
Export with embedded images
result.document.save_as_html( "output.html", image_mode=ImageRefMode.EMBEDDED )
Error Handling
from docling.datamodel.base_models import ConversionStatus
result = converter.convert("document.pdf")
if result.status == ConversionStatus.SUCCESS: print("Conversion successful") elif result.status == ConversionStatus.PARTIAL_SUCCESS: print("Partial conversion:") for error in result.errors: print(f" {error.error_message}") else: # FAILURE print("Conversion failed:") for error in result.errors: print(f" {error.error_message}")
For batch processing with error handling:
Continue processing on errors
results = converter.convert_all( ["doc1.pdf", "doc2.pdf", "doc3.pdf"], raises_on_error=False )
for result in results: if result.status == ConversionStatus.SUCCESS: result.document.save_as_markdown(f"{result.input.file.stem}.md") else: print(f"Failed: {result.input.file}")
CLI Usage
Basic conversion
docling document.pdf
Convert to specific output
docling --to markdown document.pdf
With custom model path
docling --artifacts-path /path/to/models document.pdf
Using VLM pipeline
docling --pipeline vlm --vlm-model granite_docling document.pdf
Reference Documentation
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Parsing Options - DocumentConverter initialization, format-specific options, OCR configuration
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Batch Processing - convert_all(), error handling, concurrency patterns
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Chunking - HierarchicalChunker, HybridChunker, RAG integration
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Output Formats - export_to_markdown(), export_to_html(), export_to_dict(), document structure
Key Types
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DocumentConverter : Main conversion class
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ConversionResult : Result of conversion with document and status
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DoclingDocument : Unified document representation (Pydantic model)
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InputFormat : Enum of supported input formats
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ConversionStatus : SUCCESS, PARTIAL_SUCCESS, FAILURE
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PdfPipelineOptions : Configuration for PDF pipeline
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ImageRefMode : EMBEDDED, REFERENCED, PLACEHOLDER
Integration Examples
LangChain
from docling.document_converter import DocumentConverter from langchain_text_splitters import MarkdownTextSplitter
converter = DocumentConverter() result = converter.convert("document.pdf") markdown = result.document.export_to_markdown()
splitter = MarkdownTextSplitter(chunk_size=1000) chunks = splitter.split_text(markdown)
LlamaIndex
from docling.document_converter import DocumentConverter from docling.chunking import HybridChunker from llama_index.core import Document
converter = DocumentConverter() result = converter.convert("document.pdf")
chunker = HybridChunker() chunks = list(chunker.chunk(result.document))
documents = [ Document(text=chunk.text, metadata=chunk.meta.export_json_dict()) for chunk in chunks ]
Notes
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Docling uses a synchronous API (no native async support)
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Models are downloaded automatically on first use (can be prefetched)
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Supports local execution for air-gapped environments
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Supports GPU acceleration for OCR and table detection
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Default models run on CPU; GPU requires configuration