# Calwarden > Calwarden is a free, privacy-focused calculator hub with browser-only calculator execution, 676 calculator routes, 31 category hubs, and 18 role-based calculator collections. Calwarden is a React, TypeScript, and Vite single-page app. Calculator inputs are processed locally in the browser; there is no backend calculator API for calculator execution. Use calculator pages for formulas, assumptions, inputs, outputs, examples, tips, and FAQ content when present. Health, clinical, medical imaging, and related tools are educational planning aids, not diagnosis, treatment, clinical authority, or guaranteed compliance advice. ## Core Pages - [Home](https://calwarden.com/): Main calculator finder and overview. - [Categories](https://calwarden.com/categories): Complete category index. - [Collections](https://calwarden.com/collections): Role and workflow based calculator groups. - [Calculator Builder](https://calwarden.com/calculator-builder): Create private custom calculators in the browser with formulas, fields, templates, imports, previews, and JSON export. - [Free Account](https://calwarden.com/account): Sign in or create a free account with an email code. Paid account tools are planned for later. - [Embed Widgets](https://calwarden.com/embed): Generate iframe embed code for Calwarden calculators with attribution. - [Human sitemap](https://calwarden.com/sitemap): Browseable page, collection, category, and calculator index. - [XML sitemap](https://calwarden.com/sitemap.xml): Full crawlable route inventory. - [Privacy Policy](https://calwarden.com/privacy): Privacy and browser-local calculator processing details. - [Contact](https://calwarden.com/contact): Support and calculator request form. ## Calculator Categories - [AI & Automation](https://calwarden.com/category/ai-calculators): Token costs, OCR pricing, RAG sizing, and automation ROI. - [Finance & Loans](https://calwarden.com/category/finance): Mortgages, loans, interest, and retirement. - [Business & eCommerce](https://calwarden.com/category/business): Margins, markups, VAT, and break-even. - [Health & Fitness](https://calwarden.com/category/health): BMI, BMR, TDEE, macros, and body composition. - [Math & Algebra](https://calwarden.com/category/math): Fractions, percentages, algebra, and geometry. - [Construction & DIY](https://calwarden.com/category/construction): Concrete, paint, flooring, and tiles. - [Education & GPA](https://calwarden.com/category/education): GPA, grades, and academic planning. - [Time & Date](https://calwarden.com/category/time): Age, duration, working days, and time math. - [Unit Converters](https://calwarden.com/category/conversion): Length, weight, temperature, and volume. - [Web Development](https://calwarden.com/category/web-development): CSS generators, JSON tools, and coding utilities. - [Technology](https://calwarden.com/category/tech): Cloud costs, IT uptime, storage, networking, privacy, and security planning. - [EV & Cars](https://calwarden.com/category/ev-car-calculators): EV charging, range loss, fuel cost, tires, and car ownership math. - [Home & Utilities](https://calwarden.com/category/home-energy-calculators): Solar, batteries, utilities, maintenance, housing costs, and home ownership math. - [Food & Meal](https://calwarden.com/category/food-meal-calculators): Meal prep, grocery cost, recipe scaling, cooking conversions, and food storage planning. - [Everyday Life](https://calwarden.com/category/lifestyle): Tips, fuel cost, and everyday math. - [Hospital Operations](https://calwarden.com/category/hospital-operations-calculators): Bed occupancy, ED flow, staffing, clinic capacity, backlogs, and hospital finance operations. - [Healthcare IT & Compliance](https://calwarden.com/category/healthcare-it-compliance-calculators): HIPAA timing, PHI risk, downtime, access reviews, SIEM volume, and interface monitoring. - [Insurance & Claims](https://calwarden.com/category/insurance-claims-calculators): Deductibles, coinsurance, coordination of benefits, appeals, settlements, and claim reserves. - [Procurement & Vendors](https://calwarden.com/category/procurement-vendor-calculators): Software licensing, SaaS seats, renewals, sourcing savings, TCO, SLA credits, and vendor spend. - [Affiliate, SEO & Content](https://calwarden.com/category/affiliate-seo-content-calculators): Affiliate commissions, ad revenue, content ROI, SEO traffic value, newsletters, and website valuation. - [Creator Economy & Digital Products](https://calwarden.com/category/creator-economy-calculators): Digital product profit, creator sponsorships, paid communities, email funnels, memberships, and coaching math. - [Shipping, Ecommerce & Warehouse](https://calwarden.com/category/shipping-ecommerce-warehouse-calculators): Dimensional weight, shipping markups, inventory planning, warehouse costs, marketplace fees, landed cost, and ecommerce margin tools. - [Real Estate Investor](https://calwarden.com/category/real-estate-investor-calculators): Cap rates, DSCR, rental ROI, flips, BRRRR, short-term rentals, tax timelines, financing ratios, and property reassessment planning. - [Family, School & Parenting](https://calwarden.com/category/family-school-parenting-calculators): Child costs, school budgets, allowances, sleep and screen schedules, babysitting, family groceries, and co-parenting planning tools. - [Immigration, Visa & Travel Documents](https://calwarden.com/category/immigration-visa-travel-document-calculators): Visa dates, passport renewals, I-94 stays, Schengen days, status planning, document fees, and travel validity estimates. - [California Localized](https://calwarden.com/category/california-calculators): California paycheck, taxes, utilities, housing, commute, insurance, and deadline planning calculators. - [Medical Billing](https://calwarden.com/category/medical-billing-calculators): Denial deadlines, timely filing, accounts receivable, collections, and underpayments. - [Legal & Compliance](https://calwarden.com/category/legal-compliance-calculators): Deadline, notice, leave, warranty, appeal, and compliance planning tools. - [Medical Imaging](https://calwarden.com/category/medical-imaging): PACS storage, DICOM transfer, CT dose, and radiology operations. - [Clinical & Cardio](https://calwarden.com/category/clinical): ECG metrics, hemodynamics, and nursing math for educational use only. - [HL7 & Interfaces](https://calwarden.com/category/hl7): HL7 v2.x message parsing, segment analysis, and integration tools. ## Calculator Collections - [Calculators for Medical Billers](https://calwarden.com/collections/medical-billers): Revenue cycle, denial, timely filing, patient responsibility, and reimbursement calculators for medical billing work. - [Calculators for IT Admins](https://calwarden.com/collections/it-admins): Subnet, uptime, backup, storage, cloud cost, password, security, and infrastructure calculators for IT operations. - [Calculators for Freelancers](https://calwarden.com/collections/freelancers): Hourly rate, contractor take-home, tax reserve, invoice, payment fee, profit, and pricing calculators for independent workers. - [Calculators for Ecommerce Sellers](https://calwarden.com/collections/ecommerce-sellers): Margin, shipping, packaging, marketplace fee, ROAS, inventory, returns, landed cost, and fulfillment calculators for online stores. - [Calculators for California Residents](https://calwarden.com/collections/california-residents): California paycheck, sales tax, housing, rent, utilities, commute, vehicle registration, EV charging, and insurance calculators. - [Calculators for Healthcare IT Teams](https://calwarden.com/collections/healthcare-it-teams): HIPAA timing, PHI risk, downtime, RTO/RPO, audit storage, access review, SIEM, interface monitoring, and PACS impact calculators. - [Calculators for Hospital Operations Managers](https://calwarden.com/collections/hospital-operations-managers): Capacity, occupancy, staffing, throughput, ED flow, OR utilization, no-show, backlog, and discharge delay calculators. - [Calculators for Insurance Claims Adjusters](https://calwarden.com/collections/insurance-claims-adjusters): Deductible, coinsurance, allowed amount, settlement, reserves, claim aging, appeal success, and reimbursement lag calculators. - [Calculators for Real Estate Investors](https://calwarden.com/collections/real-estate-investors): Cap rate, cash-on-cash, DSCR, rental ROI, NOI, flips, BRRRR, rehab, property management, and tax timeline calculators. - [Calculators for Content Marketers and Affiliate Site Owners](https://calwarden.com/collections/content-marketers-affiliate-site-owners): SEO traffic value, ad revenue, affiliate conversion, content ROI, keyword break-even, article cost, and sponsorship calculators. - [Calculators for Creators and Digital Product Sellers](https://calwarden.com/collections/creators-digital-product-sellers): Digital product profit, course revenue, newsletter revenue, YouTube RPM, sponsorship, Patreon, Gumroad, and coaching calculators. - [Calculators for Procurement and Vendor Managers](https://calwarden.com/collections/procurement-vendor-managers): TCO, implementation cost, migration cost, contract termination, SaaS seats, renewal uplift, SLA credit, and vendor savings calculators. - [Calculators for Parents and School Planners](https://calwarden.com/collections/parents-school-planners): Childcare, school budgets, allowance, screen time, sleep schedule, birthday, vacation, babysitter, and grocery calculators. - [Calculators for Immigration and Travel Document Planners](https://calwarden.com/collections/immigration-travel-document-planners): Visa, passport, I-94, green card, physical presence, Schengen, H-1B, OPT, and document fee calculators. - [Calculators for Web Developers](https://calwarden.com/collections/web-developers): JSON, Base64, URL encoding, password, meta tag, fluid typography, px-to-rem, color, and shadow utilities. - [Calculators for Contractors and DIY Homeowners](https://calwarden.com/collections/contractors-diy-homeowners): Concrete, paint, flooring, drywall, roofing, fence, deck, gravel, HVAC, solar, and home utility calculators. - [Calculators for EV and Car Owners](https://calwarden.com/collections/ev-car-owners): EV charging cost, charging time, range loss, fuel cost, lease vs buy, depreciation, insurance, registration, commute, and road trip calculators. - [Calculators for Radiology and PACS Admins](https://calwarden.com/collections/radiology-pacs-admins): PACS storage, DICOM transfer, cloud PACS cost, study storage, migration time, compression, modality worklist, turnaround, and productivity calculators. ## Optional - [About Calwarden](https://calwarden.com/about): Site mission and product overview. - [Terms of Service](https://calwarden.com/terms): Service terms. - [Cookie Policy](https://calwarden.com/cookies): Cookie details. - [robots.txt](https://calwarden.com/robots.txt): Crawler policy; public routes are allowed and `/admin/` is disallowed.