ConverterHQ
ConverterHQ

Internet-scale file conversion.

Sign in

Convert anything, at global scale.

200+ formats and automation APIs that feels instant.

CONVERT

From

To

Drop files or choose a source

Upload multiple files at once, mix formats, and fine-tune every conversion with format-aware settings.

Max 2GB per file · Drag & drop ready · Mixed file types welcome

STRUCTURED DATA

.OPF

Open Package Format Converter

Convert Open Package Format files with ConverterHQ using workflows tuned for other compatibility, predictable output, and practical downstream use.

Created: 1999active1 extensions

Quality and compatibility profile

Core technical and historical facts used for conversion quality, compatibility decisions, and SEO uniqueness.

FeatureFact sheet
CategorySTRUCTURED DATA
Extensionsopf
MIME typesapplication/oebps-package+xml
Created1999
InventorInternational Digital Publishing Forum (IDPF)
Statusactive
Xml Based
Epub Package Document
Metadata Container
Manifest And Spine
Transparency support
Animation support
Layer support
Vector scaling
Reflowable text
Multitrack content
Camera raw data
HDR content
Structured data
Streaming delivery

About this format

Open Package Format format context

Format: Open Package Format

Overview

OPF matters because EPUB and earlier Open eBook workflows needed a package document that could declare publication metadata, list resources in a manifest, and define the default reading order through a spine.

Ebook publishers needed one XML package file that could bind together publication metadata, content resources, and reading order for portable digital books.

OPF remains the package-document core of EPUB production, validation, conversion, and archive workflows even as surrounding EPUB features evolve.

Open Package Format is closely associated with W3C (formerly IDPF).

Open Package Format is usually selected for workflows that center on system exchange, automation, specialized interoperability.

Typical Workflows

  • system exchange
  • automation
  • specialized interoperability

Common Software

  • EPUB authoring tools
  • EPUBCheck
  • Calibre
  • digital publishing pipelines

Strengths

  • Centralizes metadata, manifest, and spine information for an EPUB publication.
  • Provides the durable packaging model that ebook toolchains and validators expect.
  • Carries forward across multiple generations of the EPUB ecosystem.

Limitations

  • Useful only inside an ebook packaging workflow rather than as a general-purpose XML container.
  • Compatibility details vary across EPUB 2, EPUB 3, and legacy-reading-system expectations.

Related Formats

  • EPUB
  • NCX
  • XML
  • HTML

Interesting Context

OPF began in the Open eBook era, evolved through IDPF EPUB specifications such as OPF 2.0.1, and is now carried forward by the W3C EPUB package-document model.

EPUB ebook production ecosystem: Calibre, Sigil, Adobe InDesign EPUB export, and all ebook authoring tools.

OPF is a required component inside every EPUB ZIP container file.

Status: active. Introduced: 1999. Invented by: International Digital Publishing Forum (IDPF). Stewarded by: W3C (formerly IDPF).

How Open Package Format fits into workflows

Workflow role: Open Package Format

EPUB ebook package authoring, ebook metadata management, and ebook production pipelines that generate or process EPUB package documents.

History of Open Package Format

Format history: Open Package Format

OPF began in the Open eBook era, evolved through IDPF EPUB specifications such as OPF 2.0.1, and is now carried forward by the W3C EPUB package-document model.

Original problem: Ebook publishers needed one XML package file that could bind together publication metadata, content resources, and reading order for portable digital books.

Why Open Package Format still matters

Current role: Open Package Format

OPF matters because EPUB and earlier Open eBook workflows needed a package document that could declare publication metadata, list resources in a manifest, and define the default reading order through a spine.

Modern role: OPF remains the package-document core of EPUB production, validation, conversion, and archive workflows even as surrounding EPUB features evolve.

When to use Open Package Format

  • system exchange
  • automation
  • specialized interoperability

Advantages of Open Package Format

  • Centralizes metadata, manifest, and spine information for an EPUB publication.
  • Provides the durable packaging model that ebook toolchains and validators expect.
  • Carries forward across multiple generations of the EPUB ecosystem.

Limitations of Open Package Format

  • Useful only inside an ebook packaging workflow rather than as a general-purpose XML container.
  • Compatibility details vary across EPUB 2, EPUB 3, and legacy-reading-system expectations.

Formats related to Open Package Format

Open Package Format technical profile

FeatureFact sheet
Categoryother
Extensions.opf
MIME typesapplication/oebps-package+xml
Created year1999
InventorInternational Digital Publishing Forum (IDPF)
Statusactive
xml_basedTrue
epub_package_documentTrue
metadata_containerTrue
manifest_and_spineTrue
supports_transparencyFalse
supports_animationFalse
supports_layersFalse
supports_vector_scalingFalse
supports_reflowable_textTrue
supports_multitrackFalse
camera_rawFalse
hdr_capableFalse
structured_data_capableTrue
streaming_readyFalse
sources{'url': 'https://en.wikipedia.org/wiki/EPUB', 'title': 'Open Packaging Format', 'relevance': 'EPUB standard context', 'source_type': 'reference'}, {'url': 'https://www.w3.org/TR/epub-33/', 'title': 'EPUB 3 specification', 'relevance': 'Current specification', 'source_type': 'official'}

Open Package Format quality and compatibility

Format profile: Open Package Format

Size profile: depends. Quality profile: depends. Editability profile: moderate. Compatibility profile: moderate. Archival profile: moderate. Metadata profile: moderate. Delivery profile: moderate. Workflow profile: exchange. Status: active.

Notable capabilities: reflowable text, structured data.

Software that opens Open Package Format

  • EPUB authoring tools
  • EPUBCheck
  • Calibre
  • digital publishing pipelines

Conversion options

Convert Open Package Format to

FAQs

Q: What is Open Package Format typically used for?

A:

Open Package Format is commonly used for system exchange, automation, specialized interoperability.

Q: What are the advantages of Open Package Format?

A:

Open Package Format is broadly compatible across common software.

Q: What should I watch out for when converting Open Package Format?

A:

Check output quality and compatibility on representative sample files.

Suggested links

Formats

Sources

Open Packaging Format

EPUB standard context

EPUB 3 specification

Current specification