file extension QSD - Quicken data file
File type specification:
File type data not available.
Extension icon: 
.QSD
File extension QSD description:
Quicken stores your data in five separate files, similar to your word processing or spreadsheet files. Quicken's data file is the electronic equivalent of the filing cabinet, drawers, and paper folders you use to store your checking account and credit card statements.
The granddaddy of the group is the one with the .qdf file extension. It contains your account information and transactions. In the folder with the .qdf file, you'll also find files with the same filename but different file extensions: .qel, .qph, .qsd, and .qtx. Quicken updates these other files behind the scenes, and there's no need to worry about what they do. In fact, you could even delete these additional files, only to find that the program recreates them the next time you open the .qdf file.
Associated applications to file extension QSD:
Company / developer:
Intuit Inc.
Quicken
Quicken helps you track, plan and manage your finances and assets — from basic budgeting and bill paying to complex investing to cataloging your belongings.