Astronomy
Plan observations with local sidereal time, optional nutation, precessed coordinates, and altitude/azimuth slots.
astronomical-sidereal-time-precession-plannerMath & Numbers
Convert illuminance between lux (lx = lm/m², SI base), kilolux (1 = 1000 lx), footcandle (1 = 10.7639104 lx), phot (1 = 10000 lx), and nox (1 = 0.001 lx). Converts via lux to the target unit and lists the equivalent value in all five units for reference. Reference values: full moon ≈ 0.25, office lighting ≈ 300–500, overcast day ≈ 1000, direct sunlight ≈ 100000 lux.
illuminance-converterMath & Numbers
Convert sound power between linear units (W, mW, µW, pW) and the decibel sound power level dB Lw (Lw = 10·log₁₀(W / 1 pW), reference P₀ = 1 pW = 1e-12 W, per ISO 3744 / IEC 60027-3). Supports bidirectional linear↔logarithmic conversion and reports the equivalent value in all five units. Reference values: whisper ≈ 1e-9 W (Lw ≈ 30), speech ≈ 1e-5 W (Lw ≈ 70), jet engine at 1 m ≈ 1e4 W (Lw ≈ 160).
sound-power-level-converterMath & Numbers
Convert sound pressure between linear units (Pa, µPa, µbar, mbar) and the decibel sound pressure level dB SPL (Lp = 20·log₁₀(p / 20 µPa), reference p₀ = 20 µPa = 2e-5 Pa RMS, per ISO 1683). Supports bidirectional linear↔logarithmic conversion. Calibration anchor: 1 Pa → 20·log₁₀(1/2e-5) ≈ 94 dB SPL. Reference values: threshold of hearing 20 µPa (0 dB), speech ≈ 0.02 Pa (60 dB), rock concert ≈ 20 Pa (120 dB), pain threshold ≈ 200 Pa (140 dB).
sound-pressure-level-converterMedia
Normalize a batch of podcast episodes, apply metadata and chapters, and package validated delivery files in one ZIP.
audio-batch-podcast-publisher-packMedia
Check podcast or spoken-audio files against platform delivery profiles, including codec, loudness, metadata, chapters, cover art, and decodability.
audio-platform-delivery-checkerFormat Conversion
Parse CSV/Excel-CSV/TSV (auto dialect, RFC 4180) into MySQL/PostgreSQL/SQLite/SQL Server INSERT batches with type inference and ON CONFLICT/IGNORE
csv-flavor-to-sql-insert-emitterMedia
Compare narration audio with its manuscript and download a timestamped pickup list for missing, extra, or changed wording.
audio-audiobook-manuscript-proofreaderMedia
Find exact and near-duplicate audio across uploaded files or a ZIP, including copies saved with different codecs.
audio-duplicate-library-finderMath & Numbers
Uniform corrosion rate by weight loss per ASTM G1: CR (mm/a) = 87.6 × ΔW / (ρ × A × t), with ΔW in mg, ρ in g/cm³, A in cm², t in hours. Also reports mpy (mils/year = mm/a × 39.37) and an indicative NACE-style carbon-steel rating (excellent/good/fair/poor). Used for immersion tests and coupon exposure.
corrosion-rate-calculatorMath & Numbers
Convert convective heat transfer coefficient (film coefficient h) between W/(m²·K) (watt per square metre-kelvin, SI base, = W/(m²·°C)) and kcal/(m²·h·°C) (1 = 1.1627778 W/(m²·K)). Converts via W/(m²·K) and lists both equivalents. h depends on flow regime and surface, not material. Typical ranges: natural-convection air ≈ 5–25, forced air ≈ 25–250, still water ≈ 100–1000, boiling/condensing water ≈ 2500–50000+ W/(m²·K).
heat-transfer-coefficient-converterMath & Numbers
Convert specific heat capacity between J/(kg·K) (joule per kilogram-kelvin, SI base, = J/(kg·°C)), kcal/(kg·°C) (1 = 4186.8 J/(kg·K)), and BTU/(lb·°F) (1 = 4186.8 J/(kg·K)). Key identity: 1 kcal/(kg·°C) = 1 BTU/(lb·°F) — numerically equal because the energy/mass·temperature factors cancel. Converts via J/(kg·K) and lists all three equivalents. Reference values: water ≈ 4186, air cp ≈ 1005, aluminum ≈ 900, iron ≈ 450 J/(kg·K).
specific-heat-converter