Updated: 12/4/2025
... create custom demographic-economic files from Web-based datasets
... use structured, menu-based API tools to extract data you need
... for both developers & users with no coding experience
... DEDE updated frequently
Did you know? there are 9,129 census tracts in California, and that
.. among all California tracts, tract 06073018700 (in San Diego County)
.. has the largest population, an estimated 40,481
.. tract average is 4,000 .. this is a very large population tract due to
.. based on the ACS2023 5-year estimates.
Quick Start
Click here to install DEDE (Windows computer) .. requires userid and password
Start DEDE using desktop icon
Start-up view shows view below
How to create a data file that you can use in the grid and save as a file for further use.
To create a California all tracts data file using ACS2022 5-year estimates, proceed as follows:
Change top right Query edit box to stab='CA' (empty edit box to run all U.S.)
Click Start button (control panel at left)
.. Results are displayed in grid .. one row for each tract in California
.. See in statusbar (bottom of form) there are 9,129 tracts in California.
Dbl-click the TotPopA22 header cell -- twice -- to sort grid in descending on this column
Note in the grid, the total population (TotPopA22) is 38,907 for tract 06073018700 or 06-073-018700
The results were written to the GIS friendly dbf file named in the Output File Path/Name.
.. integrate this dbf file into a shapefile for use with any Geographic Information System GIS
DEDE Startup View
What is in the above view/graphic? -- it is the DEDE user interface screen/form. Here are the main elements:
.. at the top is a toolbar that is also the main menu.
.. to the upper left is the Control Panel, enabling you to guide operations.
.. below the Control Panel is Notepad providing messaging and results of grid operations.
.. below the Notepad is Report Control Panel, enabling you to create reports.
.. at the bottom of the user interface is the statusbar, providing information on the status of various tasks.
.. at the right, majority of the interface, is the grid that displays data you retrieve.
- in the startup view, data are shown for census tracts in Washington, DC
- each row contains data for a census tract.
.. above that is the Files panel, that specifies subject matter input and output.
.. more on these interface components and how to use them in this guide.
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Updated: 12/4/2025