Text Processing

Convert between letters and numbers (A=1, B=2, … Z=26) with configurable separator and case, decode numbers back to letters, and compute the letter sum of any text.

Media

Upload an STL, OBJ, GLB or glTF model: exact vertex/triangle counts, bounding-box dimensions, materials, animations and node tree, plus an interactive Three.js viewer (rotate, zoom, shaded/wireframe/normals).

Health

Calculate the alveolar-arterial O₂ gradient to distinguish hypoxemia causes. PAO₂ = FiO₂×(P_atm−47) − PaCO₂/0.8; A-a = PAO₂ − PaO₂. Normal ≈ (Age+10)/4. Elevated → V/Q mismatch, shunt, diffusion impairment. Derived from StatPearls, LITFL, Cornell PICU, and Martin 1999. Not medical advice.

Health

Calculate the Absolute Neutrophil Count (ANC) = WBC × (segmented % + band %) / 100. Unit selectable: cells/µL or ×10⁹/L (1 ×10⁹/L = 1000 cells/µL). Adult reference ≥ 1500 cells/µL. Neutropenia risk strata: mild 1000–1500, moderate 500–1000, severe < 500 (agranulocytosis < 200) — high risk of serious infection, and febrile neutropenia is a medical emergency. Clinical uses: chemotherapy cycles typically require ANC ≥ 1500 to proceed and ≥ 500 for discharge from protective isolation; carbimazole/clozapine monitoring; congenital neutropenia workup. Neutrophilia > 7500 suggests bacterial infection, inflammation, steroids, or a myeloproliferative neoplasm. If only segmented % is reported, set band % to 0; if the instrument reports an absolute neutrophil count directly (NE#), this tool is not needed. Based on ASCO/IDSA neutropenia guidance, Boxer ASH 2012, and MDCalc. Not medical advice.

Science & Education

Plot an acid–base titration curve, mark buffer and equivalence landmarks, and explain the Henderson–Hasselbalch steps.

Math & Numbers

Compute the total, sensible, and latent capacity of an air-handling-unit (AHU) coil from the entering/leaving air state and the dry-air mass flow ṁ_da. Total capacity Qt = ṁ_da·(h1 − h2); sensible capacity Qs = ṁ_da·cp_ma·(T1 − T2) with cp_ma ≈ 1.006 + 1.86·W [kJ/(kg da·K)]; latent capacity Ql = Qt − Qs; Sensible Heat Ratio SHR = Qs / Qt. Each state is described by dry-bulb T plus one humidity input (relative humidity φ, or humidity ratio W); W is derived from the Magnus saturation fit when RH is supplied, and enthalpy h = 1.006·T + W·(2501 + 1.86·T) [kJ/kg da]. Signed result — works for cooling or heating coils.

Math & Numbers

Compute complex admittance Y = 1/Z = G + jB for series or parallel RLC circuits: G = R/|Z|², B = −X/|Z|². Returns conductance, susceptance, magnitude and phase angle. Supports any subset of R/L/C.

Math & Numbers

Calculate the Rankine active earth pressure on a smooth vertical wall backfilled with cohesionless soil. K_a = tan²(45°−φ/2). Optional uniform surcharge q. Returns the base pressure p₀, the total force P, and the resultant height.

AI Tools

Generate up to 10 creative domain names with AI and filter out already-registered ones via DNS + RDAP.

Games

Classic 2048. Arrow keys or swipe to slide and merge equal numbers. Each valid move spawns a tile; score accumulates from merges. 4×4 / 5×5 / 6×6 boards, pick a goal tile.

Data Analysis

Compute conversion-rate or mean differences, 95%/99% confidence intervals, two-sided p-values (Z-test for proportions, Welch t for continuous metrics), lift, sample size for 80%/90% power, recommended experiment days, plus sequential-testing and Bonferroni multiple-comparison warnings.

Text Processing

Turn a phrase into an acronym or initialism. Choose contributing words, which letter(s) to take, the separator, and the case.