Calculates unit contribution and margin from supplied selling price, unit costs and payment fee percentage. Excludes tax, fixed overhead and costs not entered; this is a scenario worksheet. Uses explicitly supplied structured inputs. Server computations are transient; the standalone website computes locally in your browser. Review the output before exporting it. No persistent account records, external source retrieval, sending, transactions or paid model calls. CSV/JSON review and export are available on the standalone website. MCP requests are capped at 128 KiB and computed responses at 256 KiB; individual field and record limits also apply.