WattShed Trace
The same address, in two programs. Now you know.
Load each program's application export as its own CSV, or one export with a program column, and tell this tool which columns are the address and, if you have it, the application ID. It normalizes every address, groups the ones that land on the same building, and shows you which addresses show up more than once, including matches that only differ by an apartment or unit number, computed in this browser from your own exports. Addresses are processed in this browser only and are never uploaded.
Matching is heuristic address normalization, not certified address validation. It does not confirm an address is real, and it is not a USPS or CASS-certified match.
An overlap is worth review, not a finding of fraud. Cross-program overlap can be entirely legitimate: a different measure, a different program year, or a household that qualified for both on its own merits.
1. Choose how programs are loaded
One file per program, or one file with a program column
Pick whichever matches how your exports actually come out of your systems.
Addresses are processed entirely in this browser tab. They are never uploaded, and nothing is stored.
2. Add program exports
No programs added yet
Add one CSV at a time. Each gets its own editable program label and column mapping.
Add a program export to see the report here.
No files handy? Load the example data to see two programs and their overlaps first.
Related tools
How matching works
Text normalization, not address verification.
Normalization
Each address is lowercased, trimmed, and stripped of punctuation. Common suffixes and directionals are standardized (St to Street, Ave to Avenue, N to North, and similar), and extra whitespace is collapsed, so two exports that spell the same address differently still land on the same comparison key.
Unit stripping
Apartment, suite, unit, and floor numbers are dropped from the comparison key. 42 Oak Avenue and 42 Oak Avenue Unit 3 point at the same building, so they are grouped together and flagged as a unit variant, not treated as a mismatch or silently merged without a note.
What this does not claim
This is heuristic text matching, not certified address validation: it does not verify a real address exists, does not use USPS or CASS certification, and does not geocode anything. A matched address is worth a closer look, not a finding of fraud, and an overlap across two programs can be entirely legitimate: different measures, different years, or a household that qualified twice on its own merits.
Nothing beyond the address, ID, and program columns you map is read for this check. If your export carries applicant names or other sensitive columns, they load into this browser tab like the rest of the file and are never sent anywhere, but you are still handling that data, so treat each export the way your programs already require.