LWP (Lotus Word Pro Document)
The native document format of Lotus Word Pro, IBM's word processor that competed directly with Microsoft Word throughout the late 1990s and 2000s.
| Full name | Lotus Word Pro Document |
| Extension | .lwp |
| MIME type | application/vnd.lotus-wordpro |
| Developer | Lotus Development Corporation (later IBM Lotus Software) |
| Released | 1995 (with Lotus Word Pro 96 Edition) |
| Type | Document |
| Container | Bento object container (binary) |
| Platform | Microsoft Windows, IBM OS/2 Warp |
What is a LWP file?
LWP is the native file format of Lotus Word Pro, a word processor sold as part of the Lotus SmartSuite office suite. Lotus Development Corporation introduced it in 1995 alongside the Word Pro 96 Edition, replacing the older Ami Pro format. IBM continued developing the format after acquiring Lotus in 1995, until the product was discontinued in 2014.
An LWP file stores a full word-processing document including text, formatting, tables, images, and layout information in a binary Bento object container. Bento is a compound document container technology that bundles multiple data streams into a single file. The format supported advanced features for its era, such as document revisions, styles, and embedded objects. Because it is a proprietary binary format without a published open specification, support outside of Lotus and IBM software has always been limited.
History
Word Pro grew out of Ami Pro, a word processor that Lotus acquired when it bought Samna Corporation in 1990. When Lotus rebuilt the application as a 32-bit product in 1995, it introduced the new .lwp format to support the expanded capabilities. IBM acquired Lotus in 1995 and continued shipping Word Pro as part of SmartSuite through version 9.8 (released 2007), before officially discontinuing the product in 2014.
How it works
LWP files are binary and use a Bento object container, which organizes content as a collection of named data streams embedded in one file. Text content, formatting rules, style sheets, embedded images, and metadata each occupy separate streams within the container. The format is not publicly documented by IBM or Lotus, which has made reverse-engineering it difficult. LibreOffice and OpenOffice attempted partial import support, though complex documents often lose formatting during conversion.
What it is used for
- Opening legacy business documents created with Lotus SmartSuite in corporate environments from the 1990s and 2000s
- Migrating archived LWP files to modern formats such as DOCX or ODF for long-term preservation
- Recovering text and content from old legal, financial, or government documents stored in LWP format
- Converting historical LWP files to PDF for read-only distribution without needing the original software
How to open it
The original Lotus Word Pro application (now discontinued) is the only software that opens LWP files without any loss. LibreOffice Writer includes a basic LWP import filter that handles many files, though complex formatting may not survive the conversion.
Pros and cons
Strengths
- Preserved rich formatting features available in Word Pro, including styles, tables, and embedded objects
- Supported both Windows and OS/2 platforms, giving it broader reach than some competitors
- Bento container structure kept all document components in a single file
- Word Pro itself could export to Microsoft Word format, easing cross-application sharing at the time
Trade-offs
- Proprietary binary format with no published specification, making third-party support unreliable
- The original application is discontinued and no longer available for purchase or download from IBM
- LibreOffice import is incomplete and drops complex formatting from many documents
- No modern application natively saves to LWP, so the format is strictly a legacy read target
Convert LWP files
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LWP FAQ
Can I open an LWP file without Lotus Word Pro?
Yes. LibreOffice Writer includes an LWP import filter that works for many files. Results vary depending on how complex the document is, but plain text and basic formatting usually come through correctly.
Who made the LWP format?
Lotus Development Corporation introduced the LWP format in 1995 with the release of Lotus Word Pro 96 Edition. IBM took over development after acquiring Lotus that same year and maintained the format until discontinuing Word Pro in 2014.
Is LWP the same as the old Ami Pro format?
No. LWP is a different format. Ami Pro used the .sam extension and a separate binary structure. When Lotus rewrote the application as a 32-bit program in 1995 and renamed it Word Pro, it introduced the new .lwp format.
What is the best way to convert an LWP file today?
Open the file in LibreOffice Writer and export it to DOCX or ODF. For files that do not import cleanly, an online LWP converter can also extract the content and produce a usable output file.