NumiHow to start a digital coin and banknote catalog
Choose the fields worth recording first, keep guesses separate from evidence, and build a catalog you can search and export.
Start with a small representative batch
Pick one tray, folder, or envelope and add a few pieces that show the range of your collection. Include something easy to identify and something that needs research. That will tell you which fields you actually use before you spend an afternoon entering data.
Start with a short title, denomination, issuer, approximate date and both sides. Add a catalog reference when you have one. For a coin, weight and diameter can help when the type is hard to distinguish. For a banknote, a series designation, issuer and signatures can be more useful than a long description of the design.
Give observations and attributions their own place
Write down what you can see, including the visible letters, measurements, or identifying marks. In the attribution fields, record the identification those observations support. If part of the inscription is unclear, preserve what you can read and explain the uncertainty in notes. Give the source enough detail that you or another collector could follow it again.
Treat the specimen in front of you as its own record. Two pieces can share the same catalog reference and still have different acquisition dates, grades, photographs, and provenance.
Use museum records to decide which fields belong in your catalog
The British Museum’s Augustus denarius R.6122 provides a useful model. R.6122 identifies one physical coin. Its record separately gives the authority, the observed weight of 3.79 g, a die axis of six o’clock, and a reference to RIC volume I, 167b. In your own inventory, assign an item identifier you control and keep the type reference in its own field. Another specimen can share the reference while having a different weight, surface, and ownership history.
Use the same distinction for paper money. The museum’s 1935 five-dollar note has its own object number, 1984,0605.351, and distinct denomination and date fields. The Bank of Canada Museum identifies 1935 as the first series from the Bank of Canada. Preserve the exact wording for issuer and issue, then record the series, signature or serial number when it helps distinguish your particular note.
Set up a row you can reuse
In a spreadsheet or an exported CSV, keep quantities and units in the header or in clearly named fields, such as weight_g and diameter_mm. Keep the catalog edition with the reference when a numbering series has changed. Give the acquisition source, date, price and currency separate fields so you can read those values later without interpreting a free-form note.
Record grades the way the source gave them, including whether the description came from you, a dealer, or a certification service. A shortlist of clear, repeatable fields makes it easier to match auction results and build a checklist later.
Keep the catalog easy to search and take with you
Use the same spelling for fields you filter on, such as mint or ruler. Use folders for groups you work with regularly and themes for checklists that cut across those groups. For instance, an emperor checklist might span two albums and a tray of duplicates.
If you’re transferring old records, compare a sample against the photographs and receipts before accepting the whole batch. Export a CSV after a major update and check a few records in the file, including any notes or purchase details that would be hard to reconstruct.