# BaseCalc HVAC Calculator > BTU CFM Duct Calculator Canonical page: [https://chrome-stats.com/d/id6786116451](https://chrome-stats.com/d/id6786116451) ## Overview - **ID:** `id6786116451` - **Platform:** Apple - **Type:** Apple app - **Status:** Available - **Publisher:** BASEMAPPED LLC - **Category:** Utilities - **Rating:** 5.00 / 5 (1 ratings) - **Version:** 1.0.1 - **Last updated:** 2026-08-30 - **First published:** 2026-07-22 - **Size:** 53 MB - **Data as of:** 2026-09-06 - **Store listing:** [Apple App Store](https://apps.apple.com/us/app/basecalc-hvac-calculator/id6786116451) - **Website:** [https://basemapped.com/products/basecalc-hvac](https://basemapped.com/products/basecalc-hvac) - **Privacy policy:** [https://basemapped.com/basecalc-hvac/privacy-policy](https://basemapped.com/basecalc-hvac/privacy-policy) ## Description HVAC field math for BTU, CFM, duct sizing, psychrometrics, manufacturer-data checks, saved history, worksheets, and materials. Pay once for Lifetime Pro — no ads. BaseCalc HVAC Calculator is an HVAC calculator for field math, worksheets, materials, and saved calculation history. Run BTU, CFM, duct sizing, airflow, psychrometrics, manufacturer-data refrigerant checks, planning load, hydronics, and other HVAC calculator arithmetic on site, then save the result for the job. 18 CALCULATORS FOR DAILY FIELD WORK • BTU ↔ Tons — convert between BTU/hr and refrigeration tons. • CFM from BTU — airflow from load and temperature rise/drop. • BTU from CFM — load from airflow and temperature difference. • Duct Sizing — round and rectangular duct from CFM and velocity. • Air Velocity — velocity from CFM and cross-sectional area. • Psychrometrics — total, sensible, and latent BTU/hr estimates at standard atmospheric pressure. • Refrigerant Lines — check entered manufacturer line data against an entered equivalent-length limit. • Superheat / Subcooling — record the exact target supplied by the equipment manufacturer. • Room Load — preliminary area-factor planning math using your supplied factor; not Manual J. • Heat Pump Balance — interpolate a bracketed balance point from entered manufacturer capacity data. • Hydronics — BTU, GPM, and ΔT relationships. • Mixed Air — mixed-air temperature from outdoor and return air. • Air Changes — ACH from CFM and room volume. • Evaporative Cooling — supply temperature and sensible air-side estimate. • Filter Velocity — filter face velocity; use manufacturer data for pressure drop. • O₂ Excess Air — theoretical dry-flue-gas dilution estimate from measured O₂; not a safety result. • Refrigerant Weight — additional charge from an entered manufacturer allowance and rate. • Outdoor Airflow — breathing-zone airflow arithmetic from user-supplied per-person and per-area rates. EVERY RESULT IS EXPLAINED • Explicit input validation, assumptions, and calculation boundaries. • Final arithmetic and a calculation breakdown where the supplied data supports one. • Saved local history so you keep a job-site record. JOB RECORDS, MATERIALS, AND WORKSHEETS • Save job contacts with site notes. • Build job worksheets with scope, quantities, and site notes. • Export worksheet PDFs for internal handoff or customer context. • Plan common pull-list items before rough-in, service, and closeout. • Send the finished billing handoff to SpeakSheet for the final invoice. DEVICE-LOCAL FOR THE FIELD • Works offline by default. • No BaseCalc account or cloud sync. • Job contacts, worksheets, settings, and calculation history use the app's local storage. • Subscription status is checked through RevenueCat; exports leave the app only when you choose to share them. • No third-party advertising SDK or third-party ads in this release. • Dark and light themes with a high-contrast job-site interface. BaseCalc HVAC is a professional reference tool. Always verify against current industry standards, manufacturer data, and local codes. The authority having jurisdiction has the final say. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ ## Rankings - #896,909 — Overall ## Similar extensions and apps - [HVAC Calculator: BTU & AC Load](https://chrome-stats.com/d/id6783446314) - [HVAC Calculator - FieldCalc](https://chrome-stats.com/d/id6784082740) - [Airflow CFM Calc HVAC](https://chrome-stats.com/d/id6764647262) - [Mean HVAC BS Tools](https://chrome-stats.com/d/id6621189879) — 5.00 / 5 - [HVAC Calculator: Load & Charge](https://chrome-stats.com/d/id6762048483) - [CaptiveAire Toolbox](https://chrome-stats.com/d/id6765656560) — 5.00 / 5 - [Duct Sizer Calc HVAC](https://chrome-stats.com/d/id6764646921) - [Ductulator - Duct Calculator](https://chrome-stats.com/d/id6757307937) — 4.60 / 5 - [Duct Calculator.](https://chrome-stats.com/d/id6756908372) — 4.70 / 5 - [BaseCalc Plumbing Calculator](https://chrome-stats.com/d/id6786117253) — 5.00 / 5 - [Unit Converter HVAC](https://chrome-stats.com/d/id6764647825) - [Heat Load Calc HVAC](https://chrome-stats.com/d/id6764647208) — 5.00 / 5 --- Source: [Chrome-Stats](https://chrome-stats.com/d/id6786116451)