What it does: add the channels you run besides the campaign above (Meta, Google, TikTok, Klaviyo…), each with its own daily spend and ROAS. AdCalc blends them with this campaign into one true MER — total revenue ÷ total spend across everything. Per-channel ROAS lies when you run several at once; MER is what ties to your P&L.

Try it: click + Add channel → name it “Google”, daily spend 150, ROAS 3. Watch the MER (blended) tile in Live results update. (This overrides the simple “Other channels” fields in the Campaign panel.)

What it does: if you sell several products, run the whole calculator on their weighted average instead of one product.

Steps: 1) in the Product panel, enter a product and click Save product (name it); repeat for each SKU. 2) Each saved product appears below — give it a weight (e.g. its share of orders: 70, 30…). 3) Tick Use blended product — every metric now runs on the blended economics. Untick to return to the single product.