Home › Merge Guides › Mercari + Reverb › Tax Prep

Merge Mercari and Reverb Sales Data for Tax Prep

At tax time you need total revenue by channel without hand-fixing each export's columns first.

Why Mercari and Reverb exports don't line up

Mercari: a sold date in the seller's local time; item price and Mercari's selling fee shown separately, with shipping often bundled into the price; an order ID tied to a single sold item. Also, like other reseller apps, the export is minimal with no tax breakdown and mixes cancelled orders into the same file.
Reverb: an order date column specific to the marketplace's order dashboard; item price, shipping, and Reverb's selling fee as separate columns, often with international currency conversion involved; an order number distinct per listing sold. Also, used mostly for musical instruments/gear, so price ranges and shipping costs vary far more per row than typical retail exports.

For tax prep, that mismatch is exactly what causes hours of manual cleanup every period.

Open CSV Experts and set your target columns once (Date, Channel, Order ID, Total).
Drop in your Mercari export and map its columns once.
Drop in your Reverb export and map it the same way — both merge into one sheet, normalized.
Export as CSV or Excel. Same-layout files merge automatically next time.

No. Everything runs in your browser using JavaScript — your files are never sent to a server.

Yes. Add as many source files as you want; each distinct file layout is mapped once and remembered.