Learn one useful thing today.
Two-way lookup with INDEX and MATCH: find a value by row and column
Retrieve a rate at the intersection of a row label and a column header by passing two exact MATCH positions into INDEX.
Read the guide →Structural Concrete Design, Flat-Plate Floors & Column FootingsTwo-Way Slab Punching Shear Critical Perimeter (b0) Formula
Calculate ACI 318 Critical d/2 Perimeter b_0 (mm) around an Interior Column, Nominal Two-Way Shear Strength V_c (kN), Factored Shear Resistance phi*V_c (kN), and Demand-to-Capacity Ratio.
Read the guide →Math & TrigTwo-way summary matrix with SUMIFS and COUNTIFS (live cross-tab table)
Build a live PivotTable-style Region x Category grid that updates automatically without manual refresh using mixed references ($E2 and F$1).
Read the guide →Lookup & ReferenceTwo-way XLOOKUP: dynamic row and column matrix lookup
Nest one XLOOKUP inside another to retrieve the intersection of a row label and a column header without hardcoded column numbers.
Read the guide →Engineering & ScienceTyn-Calus Liquid Diffusivity Correlation (Molar Volume & Surface Tension)
Estimate dilute liquid molecular diffusivity D_AB = 0.00893 * (V_B^0.267 / V_A^0.433) * (T / μ_B) * (σ_B / σ_A)^0.15 (× 10^-5 cm^2/s) without empirical association factors!
Read the guide →InformationTYPE function: classify any cell into numeric codes 1, 2, 4, or 16
Branch on cell data types in one SWITCH expression using TYPE codes (1 = Number, 2 = Text, 4 = Logical, 16 = Error).
Read the guide →Statistical & Clinical AnalysisUCSF-CAPRA Score Formula: Preoperative Prostate Cancer Risk Assessment (0 to 10)
Stratify biochemical recurrence-free and metastasis-free survival in localized prostate cancer using Matthew Cooperberg’s 5-variable UCSF-CAPRA score (0–10 points).
Read the guide →High-Vacuum, Semiconductor Tooling & Particle Accelerator Engineering, UHV Wall OutgassingUHV Chamber Outgassing Load & Ultimate Base Pressure Formula
Calculate Power-Law Wall Outgassing Gas Load Q(t) (10⁻⁶ mbar·L/s), Ultimate Chamber Base Pressure P_base (10⁻⁹ mbar), Area-Specific Pumping Speed (L/s·m²), and UHV Target Ratio.
Read the guide →Healthcare & Clinical CalculatorsUKELD Score (UK Model for End-Stage Liver Disease & >= 49 Listing Cutoff)
Calculate NHS Blood and Transplant’s SI-unit UKELD score = 5.395*LN(INR) + 1.485*LN(Creat_µmol_L) + 3.130*LN(Bili_µmol_L) - 81.565*LN(Na_mmol_L) + 435 and >= 49 transplant eligibility.
Read the guide →Membrane Separations & Bioprocess EngineeringUltrafiltration Gel-Layer Limiting Flux Formula
Calculate Volumetric Concentration Factor Retentate Concentration C_bulk = C_0 * VCF, Blatt Stagnant-Film Limiting Permeate Flux J_lim = k_m * LN(C_gel / C_bulk), Total Permeate Flow, and Gel Headroom.
Read the guide →Non-Destructive Testing (NDT), Ultrasonic Shear-Wave Weld Flaw Sizing & ASME Sec VUltrasonic NDT Weld Skip Distance & Flaw Depth Formula
Calculate V-Path Full Skip Surface Distance S = 2*T*TAN(theta) (mm), Horizontal Probe-to-Flaw Surface Projection (mm), Leg-1 vs Leg-2 True Flaw Depth Below Top Surface (mm), and Inspection Leg Number.
Read the guide →Medical Device & Automotive Polymer Joining, 20/35 kHz Ultrasonic Plastic WeldingUltrasonic Plastic Welding Horn Gain & Heating Formula
Calculate Acoustic Stack Peak-to-Peak Horn Amplitude (um), Peak Sonotrode Tip Velocity (m/s), Energy-Director Cyclic Strain Amplitude, and Viscoelastic Melt Power (W).
Read the guide →Engineering & ScienceUnderwood Minimum Reflux Ratio (Rmin) & Eduljee-Gilliland Distillation Correlation
Calculate binary saturated-liquid Underwood minimum reflux ratio R_min = (1 / (alpha - 1)) * ((xD / xF) - alpha * ((1 - xD) / (1 - xF))) and the Eduljee-Gilliland theoretical stage parameter Y = 0.75 * (1 - X^0.5668).
Read the guide →Development Economics & Welfare IndicesUNDP Geometric Human Development Index (HDI) Formula
Compute the post-2010 UNDP Human Development Index HDI = (I_Health * I_Education * I_Income)^(1/3), log-income index normalization, and uneven-development penalty vs the legacy arithmetic mean.
Read the guide →Engineering & ScienceUNIQUAC Combinatorial Activity Coefficient (Staverman-Guggenheim VLE)
Calculate the entropic size-and-shape UNIQUAC combinatorial activity coefficient γ_1^C from van der Waals volume (r_i) and surface-area (q_i) parameters in asymmetric solvent-heavy hydrocarbon or oligomer mixtures.
Read the guide →Dynamic arraysUNIQUE function: deduplicate a list vs find values that appear only once
People use the word "unique" for two different tasks: listing every name once (distinct) and isolating names that never repeated (exactly once). Control both behaviours with UNIQUE and handle empty results safely.
Read the guide →Logical & ConditionalUnit Step Threshold Gate (GESTEP Heaviside Pattern) for Quota & Tier Counting
Implement exact binary step indicators (1 when Value >= Step, 0 otherwise) to gate quota attainment, flag non-negative cash flows, and compute marginal bonus tiers without nested IF chains.
Read the guide →Private Credit, Direct Lending & Leveraged BuyoutsUnitranche First-Out / Last-Out AAL Yield Skim Formula
Model Private Credit Unitranche Agreement Among Lenders (AAL) tranche economics: Total Facility Size, First-Out Interest Skim Transferred FO*(S_blend - S_FO), Effective Last-Out Spread S_blend + (FO/LO)*(S_blend - S_FO), and Basis-Point Pickup.
Read the guide →Hepatology, Organ Transplant Allocation & Clinical ScoringUNOS MELD Liver Transplant Allocation Score Formula
Calculate Original UNOS Model for End-Stage Liver Disease (MELD) Score 9.57*LN(Cr_eff) + 3.78*LN(Bili_eff) + 11.2*LN(INR_eff) + 6.43 with mandatory 1.0 lower lab floors, 4.0 Creatinine/Dialysis ceiling, and [6, 40] clamping.
Read the guide →Engineering & ScienceUnruh Effect Temperature (TU) & Rindler Horizon Distance Formula
Calculate the Fulling-Davies-Unruh quantum vacuum thermal temperature T_U = (hbar * a) / (2 * PI() * c * k_B) (Kelvin) and Rindler causal horizon distance d_R = c^2 / a for ultrahigh laser-plasma accelerations.
Read the guide →Lookup & ReferenceUnwrap a stacked column into a 2D table of records (INDEX + ROW/COLUMN)
Reshape copy-pasted PDF or web directories where Name, Role, and Salary repeat every K rows in Column A into clean structured rows and columns.
Read the guide →Capital Markets, Up-C IPO Structuring & Tax Receivable AgreementsUp-C IPO Tax Receivable Agreement (TRA) 85% Split Formula
Calculate Up-C Partnership-IPO IRC Section 743(b) Exchange Basis Step-Up, Gross 15-Year Cash Tax Savings Created for PubCo, Contractual 85% Tax Receivable Agreement (TRA) Liability Owed to Pre-IPO Owners, and 15% Net Benefit Retained by Public Shareholders.
Read the guide →Cleaning imported dataUPPER, LOWER, and PROPER: standardize inconsistent text case
Convert SKUs to uppercase, email addresses to lowercase, and contact names to title case—while watching how PROPER capitalizes letters after hyphens and punctuation.
Read the guide →Antitrust Economics & Merger AnalysisUpward Pricing Pressure (UPP) & GUPPI Merger Screen Formula
Calculate Gross Upward Pricing Pressure Index GUPPI_1 = D_12 * (P_2 - C_2) / P_1, Farrell-Shapiro Net UPP_1, and break-even marginal-cost efficiency E_1* in horizontal merger review.
Read the guide →Engineering & ScienceUrbach Tail Sub-Bandgap Absorption & Urbach Disorder Energy (EU)
Model exponential sub-bandgap optical absorption alpha(E) = alpha_0 * EXP((E - E_0) / (E_U / 1000)) (cm^-1) and extract Urbach disorder energy E_U (meV) from two spectral points in perovskites and amorphous silicon.
Read the guide →EngineeringUSDA SCS Curve Number (TR-55) Stormwater Runoff Depth Formula
Calculate event runoff depth with the traditional TR-55 curve-number equation, including numeric input checks and the initial-abstraction threshold. Experiment with rainfall and curve number in a live worksheet.
Read the guide →Pharma Quality Assurance, Biologics Cold Chain & USP <1079> StabilityUSP <1079> Cold-Chain Mean Kinetic Temperature (MKT) Formula
Calculate Pharmaceutical Cold-Chain Haynes Mean Kinetic Temperature (MKT in °C) with Standard Activation Ratio ΔH/R = 10,000 K (83.145 kJ/mol), Nonlinear Arrhenius Bias Over Arithmetic Mean Temperature, and USP <1079> 2–8°C Excursion Gate.
Read the guide →Pharmaceutical Quality Control & GMP Release, USP <1216> Uncoated Tablet FriabilityUSP <1216> Tablet Friability & Sample Size Formula
Calculate Harmonized USP <1216> Minimum Tablet Count (6.5 g vs 10-Tablet Rule), 100-Drop Abrasion Mass Loss (mg), Percentage Friability (%), and <=1.0% GMP Release Gate.
Read the guide →FinancialUtilization, Realization, and Effective Hourly Rate formulas (agencies & law)
Decompose consulting and legal revenue leakage across Utilization %, Billing Realization %, and Collection % into Effective Hourly Rate.
Read the guide →Mechanical Power Transmission, V-Belt Sheave Drives, Pitch Length & Wrap AngleV-Belt Sheave Pitch Length & Small-Pulley Wrap Formula
Calculate Open-Drive V-Belt Pitch Length Lp (mm), Small-Sheave Arc of Contact Wrap Angle (deg), Speed Reduction Ratio (D/d), and Linear Belt Velocity (m/s).
Read the guide →Vacuum Technology, PVD/CVD Thin-Film Tools & Turbomolecular PumpingVacuum Chamber Conductance Throttling & Pumpdown Time Formula
Calculate Foreline/Valve Throttled Effective Pumping Speed S_eff (L/s), Outgassing-Limited Ultimate Base Pressure P_ult (10^-3 mbar), Pumpdown Time to Target Vacuum (s), and Throttling Loss (%).
Read the guide →Polymer Sheet Processing, Vacuum/Pressure Thermoforming & Packaging Gauge ThinningVacuum Thermoforming Areal Draw Ratio & Wall Formula
Calculate Rectangular Mold Areal Draw Ratio Ra = A_mold / A_clamp, Volume-Conserved Average Part Wall Thickness t_avg (mm), Deepest Bottom-Corner Minimum Wall (mm), and Retained Corner Gauge (%).
Read the guide →Data Validation & HygieneValidate & Highlight Dates Strictly Within the Next 30 Days (Type-Safe Window)
Enforce or highlight scheduling and renewal dates falling inside a 30-day forward window [Anchor, Anchor + 30] while rejecting text strings, blanks, and past dates.
Read the guide →LogicalValidate an Invoice Prefix, Four Digits, Allowlist and Blocklist
Audit invoice IDs as uppercase INV- plus four ASCII digits, reject reserved IDs and require literal membership in a configured uppercase currency allowlist.
Read the guide →Logical & Lookup FormulasValidate Required Row Inputs with Check Mark & Type Guard (COUNTA & ISNUMBER)
Display an instant Unicode check mark ("✓ Ready") only when all required row fields are populated and numeric amounts pass ISNUMBER—preventing Excel’s silent "text > number" comparison trap.
Read the guide →Date & Time FormulasValidate Weekday-Only Dates Within a Next-30-Days Booking Window
Enforce multi-rule scheduling validation—requiring a real numeric date inside [Anchor_Date, Anchor_Date + Window_Days] that also lands Monday–Friday via WEEKDAY(Date, 2) <= 5.
Read the guide →FinancialValue at Risk (VaR) formula: 95% / 99% Parametric VaR & √T horizon scaling
Illustrate a normal-return, zero-drift VaR estimate with daily volatility and square-root-of-time scaling.
Read the guide →TextVALUE function: convert numbers stored as text into real numbers
Turn imported numeric text strings like "145.50" or "0042" into calculable numbers with VALUE, and strip unit labels that cause #VALUE!.
Read the guide →Public Policy, Health & Labor EconomicsValue of a Statistical Life (VSL) & VSLY Formula
Calculate Thaler-Rosen / Viscusi hedonic wage-risk VSL = (Delta_w / Delta_r_100k)*100,000, micromort willingness-to-pay, and real-annuity Value of a Statistical Life-Year (VSLY).
Read the guide →Analytical Chemistry & Chromatography EngineeringVan Deemter HETP & Optimal Velocity Formula
Calculate Optimal Mobile-Phase Velocity u_opt = SQRT(B / C), Van Deemter Height Equivalent to a Theoretical Plate HETP = A + B/u + C*u, Actual Column Plates N, and Peak Theoretical Plates N_max.
Read the guide →ScienceVan der Waals Real-Gas Equation & Compressibility Factor (Z)
Compare a van der Waals model pressure with an ideal-gas calculation using consistent molar units, and compute the model compressibility factor with explicit input guards.
Read the guide →Engineering & ScienceVan Laar Activity Coefficients (gamma1 & gamma2) for Azeotropic Distillation
Calculate Johannes van Laar’s unequal-molar-volume activity coefficients gamma_1 = EXP(A_12 / (1 + (A_12 * x_1) / (A_21 * (1 - x_1)))^2) and gamma_2 for ethanol-water, isopropanol-water, and hydrocarbon VLE trays.
Read the guide →Civil, Structural & Geotechnical EngineeringVan Rijn (1984) Sediment Transport Formula: Particle Parameter D_* & Transport Stage T
Calculate Leo C. van Rijn’s (1984, Delft Hydraulics) Dimensionless Particle Parameter D_* = d_50 * (((s - 1) * g) / nu^2)^(1/3), Excess Bed-Shear Transport Stage T, and Sand Bedload Rate q_b (m^2/s).
Read the guide →Dairy Process Engineering, Van Slyke & Price Cheddar Cheese Yield & Milk StandardizationVan Slyke Cheddar Cheese Yield & Casein-Fat Formula
Calculate Milk Casein-to-Fat Ratio (C/F), Van Slyke Theoretical Cheese Yield (kg per 100 kg milk), Finished Curd Block Mass (kg), and Sweet Whey Mass Balance (kg).
Read the guide →Healthcare & Clinical Calculatorsvan Walraven Elixhauser Weighted Comorbidity Index & Inpatient Mortality
Condense ICD administrative Elixhauser comorbidity flags into Carl van Walraven’s (2009) single weighted risk score (-19 to +89) and predicted hospital mortality probability.
Read the guide →Epidemiology & Causal InferenceVanderWeele-Ding E-Value Formula for Unmeasured Confounding
Calculate the VanderWeele-Ding (2017) E-value = RR* + SQRT(RR* * (RR* - 1)) for both point risk ratios and 95% confidence limits, handling protective RR < 1 automatically.
Read the guide →ScienceVapor Pressure Deficit (VPD): Leaf-to-Air Tetens Formula (kPa)
Estimate leaf-to-air vapor pressure difference from leaf temperature, air temperature and relative humidity. Compare it with air VPD and inspect saturation and actual vapor pressures.
Read the guide →Thermodynamics, Industrial Chiller Engineering & Vapor-Compression CyclesVapor-Compression Liquid Subcooling, NRE & Mass-Flow Formula
Calculate Vapor-Compression Chiller Subcooled Net Refrigerating Effect NRE (kJ/kg), Liquid Subcooling Capacity Gain %, Required Refrigerant Mass Flow Rate m_dot (kg/s), and Cycle Cooling COP from State-Point Enthalpies.
Read the guide →StatisticalVAR.S vs VAR.P: calculate sample variance (n - 1) vs population variance (n)
Choose VAR.S when analyzing a sample of observations and VAR.P when you have every member of a closed population.
Read the guide →Financial ModelingVariable Declining Balance (VDB) Schedule with Optimal Switch to Straight-Line
Model accelerated declining-balance depreciation that automatically switches to straight-line as soon as straight-line yields a larger charge, ensuring book value reaches salvage on schedule.
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