BillingBench is the denial management and revenue cycle reference platform for medical billing professionals and practice administrators. Every figure is cited to a named primary source. Every policy citation carries the source URL, verification date, and changelog. Every modifier ruling traces to the AMA CPT guidelines, CMS transmittals, or a payer policy document retrieved directly. Free tools: No account required. The Denial Code Decoder covers 61 CARC codes with cause, fix, and exact appeal pathway. The Appeal Letter Builder generates a complete draft letter with statutory citations pre-populated for the denial type, payer, and state. The 835 ERA Parser runs client-side, users upload a remittance file and get denied claims broken down by CARC code, underpayment flags, and collection rate in seconds. The Modifier Matrix returns payer-specific rulings across 200+ verified modifier decisions covering Medicare, BCBS, and UHC, with the documentation language needed to survive an audit. Also free: 30 specialty guides, 80+ appeal templates, 16 payer profiles, prompt pay statute lookup for all 50 states, and a timely filing calculator. Workbench: Denial Operations for Billing Teams. Pro plans add the Workbench: a denial queue with appeal deadlines, daily interest accrual tracking, 835 ERA import, 13-week cash flow projection, and priority scoring by recovery value. Practice ($149/month) and Operations ($399/month) tiers add shared queues, role-based access, item assignment to individual billers, and manager analytics for departments running multiple billers. Solo starts at $49/month for individual billers. The Signal Network. Every 835 ERA uploaded contributes aggregate denial patterns to a cross-practice signal network including payer name, CARC code, and dollar totals only, no patient data. That network feeds a denial signal API used by RCM companies and healthcare software vendors. Built by an MD candidate, MS, MPH. No PHI stored. BAA available with every account.