What is the SPD file format?
.spd files are used by IBM SPSS Statistics, a statistical analysis software. .spd files store custom dialog window definitions as a ZIP archive containing the dialog's XML layout and resources. The .spd format was developed by SPSS Inc., which was acquired by IBM in 2009.
SPSS uses .spd files to store custom dialog windows created by users. These dialogs provide user-defined input forms for custom statistical functions, and can be shared as installable packages - colleagues install an .spd directly into their SPSS menus. Related formats include .sps syntax scripts and .sav data files.
Security & safety
RISK: MEDIUMAn .spd is a plugin: installing it adds a dialog that generates and can run SPSS command syntax. A malicious or careless package could therefore embed syntax that runs unintended operations within SPSS (e.g. deleting/overwriting data or invoking external commands). Treat .spd files like any installable extension: only install custom dialogs from sources you trust, and if unsure, open the .spd as a ZIP first and inspect the bundled syntax template before installing. The file is not an OS-level executable, but the syntax it runs has SPSS's privileges over your data.
Format details
in a nutshellFULL NAMESPSS Custom Dialog Packageaka IBM SPSS Statistics custom dialog, SPSS custom dialog file
DEVELOPERIBM (SPSS Statistics; SPSS originally by SPSS Inc., acquired by IBM in 2009)since IBM SPSS Statistics Custom Dialog Builder era (SPSS Statistics 17+/IBM ownership, circa 2009)
CATEGORYPlugin Files
MIME TYPEapplication/zip
TYPEZIP-based package bundling a custom dialog definition for IBM SPSS Statistics
This extension is also used by…
- Bitstream Speedo scalable font - A legacy Bitstream outline-font format (Speedo), historically used on Unix/X11 and embedded systems; this is what the database's NAME field labels .spd, but its developer/programs point to SPSS.
- Speedo / FreeType Speedo font - The Speedo font format was supported by older FreeType/X11 stacks; effectively obsolete today.
- Sage ACT! / other app data files - Various niche applications use .spd for their own data; identify by the owning program.
MAGIC BYTES · FILE SIGNATURE
OFFSET
00010203
HEX
504B0304
ASCII
PK··
Per the source description, an SPSS .spd is a single archive (ZIP) containing the custom dialog's files, so it begins with the standard ZIP signature 50 4B 03 04 ("PK"). Distinguish it from any other ZIP by its internal SPSS dialog definition (the .cfe/specification and associated resources) rather than by the magic bytes alone.
Programs that open SPD files
Windows2 apps
IBM SPSS Statistics
Paid Install the dialog, don't 'open' it: Extensions (or Utilities) > Install Custom Dialog, pick the .spd - it adds the dialog to your menus.
7-Zip (inspect only)
Open-source Open the .spd as a ZIP to inspect its contents - useful for checking what a shared dialog contains, but it won't install or run the dialog. 
macOS1 app
IBM SPSS Statistics
Paid Use Extensions/Utilities > Install Custom Dialog to add the .spd dialog. SPSS runs natively on macOS. 
Linux1 app
IBM SPSS Statistics
Paid Install the .spd via the Custom Dialog install option. SPSS Statistics is supported on Linux. Technical details
deep spec| Container format | ZIP archive; magic bytes 50 4B 03 04 ("PK") at offset 0 |
| Internal encoding | XML/text dialog specification and resource files bundled inside the ZIP |
| Byte order | Little-endian (ZIP structural fields) |
| Compression | DEFLATE per entry (ZIP standard) |
| Integrity check | CRC-32 per ZIP entry; no document-level digital signature |
| MIME type | application/zip (also application/octet-stream) |
| Typical file size | A few KB to a few hundred KB (dialog layout and resources, no statistical data) |
| Operating systems | Windows, macOS, Linux (wherever IBM SPSS Statistics is installed) |
| Created with | IBM SPSS Statistics Custom Dialog Builder (introduced circa SPSS Statistics 17) |
| Installation method | Extensions > Install Custom Dialog (.spd) in IBM SPSS Statistics |
| Package contents | Dialog layout definition (controls, labels, drop-downs), SPSS syntax template, and optional icon or resource files |
| Version compatibility | Newer SPSS Statistics releases can open .spd packages built with older Custom Dialog Builder versions |
| Encryption | None - the ZIP container is unencrypted |
| Primary purpose | Distributing and installing reusable custom analysis dialogs that extend the IBM SPSS Statistics interface |
| Released | IBM SPSS Statistics Custom Dialog Builder era (SPSS Statistics 17+/IBM ownership, circa 2009) |
| Latest version | Compiled Custom Dialog Package (.spd) used by current IBM SPSS Statistics releases |
| Specification | www.ibm.com |
SPD conversions
Possible
Not possible
Community Q&A
asked by usersNo questions yet - be the first to ask about SPD files.
Frequently asked questions
What is an SPD file?
In its dominant modern meaning it's a Custom Dialog Package for IBM SPSS Statistics - a ZIP package defining a reusable dialog box that generates SPSS syntax. You install it into SPSS to add the dialog to your menus.
How do I open or install an SPD file?
Open IBM SPSS Statistics and use Extensions (or Utilities) > Install Custom Dialog, then select the .spd. That registers the dialog in your menus. You can't usefully open it as a document outside SPSS.
Can I open an SPD file without SPSS?
You can inspect it: it's a ZIP, so an archive tool (7-Zip) will show its contents. But to actually use the dialog you need IBM SPSS Statistics - only SPSS understands and runs it.
Why does the file database call .spd a 'Speedo font'?
That NAME label refers to a legacy Bitstream Speedo outline-font format, but the same database record lists IBM as the developer and SPSS as the program - pointing to the SPSS Custom Dialog Package as the real, current meaning. Check which app made your file.
Can I convert an SPD to PDF or Word?
No - an .spd is an SPSS plugin, not a document. Those conversions don't apply. If you want a report, run the dialog in SPSS and export the resulting output (.spv) to PDF or Word.
How do I create an SPD file?
Use SPSS's Custom Dialog Builder to design a dialog, then save/export it as a Custom Dialog Package (.spd). Share that .spd with others, who install it into their own SPSS.
References
1IBM - SPSS Statistics documentationwww.ibm.com
2IBM - SPSS Statistics product pagewww.ibm.com
