Arb Radar

Spot resale deals while you browse. Values listings you view against real eBay sold prices — privately, on your device.

Arb Radar turns your normal marketplace browsing into deal-hunting. As you scroll Facebook Marketplace, Craigslist, OfferUp, or Mercari, Arb Radar quietly notes the listings you see and checks what those items actually sell for, using real eBay sold prices — not asking prices. Open the dashboard and every listing is ranked by profit spread and ROI. WHAT IT DOES • Captures listings you browse — no extra clicks, no separate searches • Values them against eBay sold comps, with accessory listings filtered out so a grill cover never prices a grill • Flags $1 "attention" listings and placeholder prices so they can't fake the top of your feed • Vehicles get real eBay Motors sold comps plus a one-click Kelley Blue Book link • Quick check: type any item name for its real resale value • Link import: paste any listing URL to pull it into your radar • Photo scan (optional): snap something in a store and identify + value it (uses your own Anthropic API key) • Your resale style: eBay fees (~13%) or local cash flips (0%) PRIVATE BY DESIGN Everything runs and stays on your device. There is no Arb Radar server, no account, no analytics. Nothing you browse is sent to us — we couldn't see it if we wanted to. Works with listings you actually view, at human browsing speed. Not affiliated with any marketplace.