Donor de-duplication
Open a gift list with donor name, email, and address columns. Records that match exactly once case, punctuation, and spacing are ignored, and near matches such as the same email under a different name spelling, are proposed as groups. Nothing is merged until you tick a group, and after merging the gift count and total are proved to be the same as before.
The gift list is read in your browser and stays on this device. Nothing is uploaded.
The file is read in this browser and is not uploaded.
These are matched from the header words. Check them and change any that are wrong. Map the email and address columns so near matches can be found.
3. Proposed merge groups
Nothing is merged until you tick a group. Pick the record to keep; the others in the group are folded into it.
After merging
Donors
Gifts and the donor record each belongs to
What gets checked
- The gift total and the gift count are the same before and after merging.
- Every gift is still listed after merging with its own row number and amount.
- Every gift belongs to exactly one donor record after merging.
- A gift changed donor record only when its record was merged away, and then to the record you chose to keep.
- Donor records before, minus the records merged away, equal donor records after, and every record that was not merged away is still listed unchanged.
- Each donor record after merging holds exactly the gifts of its own record and of the records merged into it.
- These checks are made by a separate routine that works from the list as it was before merging and shares no arithmetic with the one that applies the merges.
- Every row with data is accounted for: used, listed as left out (with its row number and the reason), or listed as unreadable. An unreadable row marks the result not verified.
How it works
- Open the list. Drop a .csv or .xlsx gift list. Each distinct combination of donor name, email, and address, exactly as written, becomes one donor record.
- Check the column mapping. Name, email, address, date, and amount are matched from the header words. Any choice can be changed.
- Review the proposed groups. Exact matches after normalizing and near matches (same email, same address, or same name with a different email or address) are shown as groups with the reason. Tick the groups that really are one donor and pick the record to keep.
- Merge and export. The ticked groups are merged, the checks are run, and the merged donor list and the gift-to-donor table can be downloaded as Excel or CSV.
Worked example
A made-up list of eight gifts totaling $845.00. Row 9 repeats row 2's donor exactly, so there are seven donor records, D1 to D7.
| Record | Name | Address | Gifts | Total | |
|---|---|---|---|---|---|
| D1 | Dana Whitcombe | dana@example.org | 3 Oak Ct, Fairview | 2 | $100.00 |
| D2 | dana whitcombe | DANA@example.org | 3 Oak Ct., Fairview | 1 | $50.00 |
| D3 | Eli Fontaine | eli@example.org | 9 Pine Way, Fairview | 1 | $200.00 |
| D4 | Elias Fontaine | eli@example.org | 9 Pine Way, Fairview | 1 | $25.00 |
| D5 | Farah Nkemelu | farah@example.org | 21 Lake Dr, Fairview | 1 | $400.00 |
| D6 | G. Nkemelu | 21 Lake Dr, Fairview | 1 | $60.00 | |
| D7 | Harper Quist | harper@example.org | 5 Hill St, Fairview | 1 | $10.00 |
Three groups are proposed: D1 and D2 (exact after normalizing), D3 and D4 (same email, different name), D5 and D6 (same address, different name). The user confirms the first two and leaves the third alone. After merging there are 5 donor records: D1 with 3 gifts and $150.00, D3 with 2 gifts and $225.00, D5 $400.00, D6 $60.00, D7 $10.00. Still 8 gifts and $845.00.
The example uses made-up names and numbers.
Questions
Does it ever merge on its own?
No. It proposes groups and shows why each pair was linked. A merge happens only for a group you tick, into the record you pick.
What counts as a near match?
The same email with a different name or address, the same address with a different name or email, or the same name with a different email or address. Case, punctuation, and extra spaces are ignored. Abbreviations are not expanded, so Street and St are different addresses to the tool.
Does it change my file?
No. Your file is only read. The merged donor list and the table showing which record each gift belongs to are new downloads.
This tool calculates and checks numbers. It is not legal, tax, or medical advice.