AnythingOnline / Free calculators and utilities

Audio, Video & Photography calculators

Choose a task below. Check each calculator’s assumptions and units before using its result.

500 Rule Calculator - Shutter Speed for Sharp Stars

Calculate the maximum exposure time before Earth rotation causes pinpoint stars to blur into elongated star trails.

BPM to Milliseconds Delay & Reverb Pre-Delay Calculator

Calculate precise tempo-synced delay times, reverb pre-delays, and decay envelopes in milliseconds and Hertz for music mixing.

Decibel Addition Calculator - Sound Pressure Level Sum

Combine multiple sound pressure levels using logarithmic decibel addition and subtract ambient background noise from acoustic measurements.

Free 555 Timer Calculator

Calculate oscillator frequency, high/low period intervals, duty cycle percentage, and monostable time delay for NE555 timer circuits.

Free Acoustic Bass Trap Depth Calculator

Calculate quarter-wave (λ/4) absorber thickness, air gap placement, and optimal material flow resistivity to absorb room modes and standing waves.

Free Acoustic Horn Flare & Cutoff Frequency Calculator

Calculate exponential horn flare cutoff frequency (fc), minimum mouth perimeter, throat expansion rate, and axial length.

Free Air Core Inductor Calculator

Calculate required coil turns, winding length, total copper wire length, and DC resistance for single-layer air-core RF and crossover inductors.

Free Audio Attenuator Calculator

Calculate exact resistor values for L-Pad, T-Pad, and Pi-Pad passive attenuation networks while maintaining perfect impedance matching.

Free Audio File Size Calculator

Estimate WAV, MP3, and FLAC uncompressed and compressed file sizes from duration.

Free Audio Limiter Threshold & Release Tempo Calculator

Calculate tempo-synced limiter release times (ms) to eliminate pumping and sub-bass distortion while dialing in gain drive for target streaming LUFS.

Free BPM to Delay & Reverb Time Calculator

Convert music tempo (BPM) into exact delay milliseconds and vocal pre-delays.

Free Camera Hyperfocal Distance Calculator

Calculate exact hyperfocal distance, near limit, and depth of field for landscape and astrophotography across all sensor formats.

Free Camera Sensor Crop Factor Calculator

Convert focal lengths to 35mm full-frame equivalent field of view and depth of field.

Free Coaxial Cable Loss Calculator

Calculate RF signal attenuation in decibels (dB), transmitted power lost as heat, and delivered watts at the antenna from HF ham radio to 5.8GHz microwave.

Free Depth of Field Calculator

Calculate near and far focus limits, hyperfocal distance for infinity landscape sharpness, and total depth of field in meters and feet.

Free Dipole Antenna Length & Resonance Calculator

Calculate half-wave dipole wire leg lengths and velocity factor adjustments.

Free Guitar Fret Placement Calculator

Calculate precision 12-tone equal temperament fret positions, fret-to-fret cut distances, and saddle intonation offsets for guitars and basses.

Free Heat Shrink Tubing Size Calculator

Select the optimal nominal heat shrink tubing diameter and shrink ratio (2:1, 3:1, 4:1) to fit over connectors and clamp down tightly on cables.

Free Heatsink Thermal Resistance Calculator

Calculate required thermal resistance (θsa) and junction temperature limits.

Free IoT Battery Life & Runtime Calculator

Estimate runtime in days and years for ESP32 and microcontrollers using duty cycles.

Free LED Series Resistor Calculator

Determine exact current-limiting resistance, nearest standard E-series resistor, and power dissipation rating to prevent LED burnout.

Free Line Array Speaker Critical Distance Calculator

Calculate line array column near-field boundary distance, high-frequency acoustic coupling limits, and SPL loss across audience depth.

Free Microphone Sensitivity & Preamp Gain Calculator

Convert between mV/Pa and dBV/Pa, calculate required clean preamp gain (dB) for speech and vocals, and check if you need an in-line booster.

Free Microphone SNR & Preamp EIN Calculator

Calculate microphone capsule self-noise, preamp Equivalent Input Noise (EIN), and overall recording audio noise floor.

Free Op-Amp Gain Calculator

Calculate closed-loop voltage gain (Av), decibels (dB), output voltage, and power supply rail clipping for inverting and non-inverting op-amp circuits.

Free PCB Trace Width Calculator

Calculate internal and external copper trace width and current limits per IPC-2152.

Free Peltier Cooler Calculator

Size thermoelectric TEC modules, calculate cold-side heat pumping capacity, hot-side dissipation, and required heatsink thermal resistance.

Free QRD Acoustic Diffuser Calculator

Calculate exact quadratic residue well depths, well width dividers, and upper/lower sound diffusion frequency cutoffs for DIY studio acoustic panels.

Free QRD Acoustic Diffuser Well Depth Calculator

Design Manfred Schroeder Quadratic Residue Diffusers (QRD): calculate prime residue sequences, exact well depths, and critical diffusion frequency limits.

Free Room Modes & Axial Standing Wave Calculator

Calculate axial, tangential, and oblique room standing waves, Schroeder cutoff frequency, and bass trap acoustic treatment targets.

Free Room Reverb Time (RT60) Calculator

Calculate Sabine RT60 reverberation decay and required acoustic treatment panels.

Free Sabine Reverberation Time (RT60) Calculator

Calculate room sound decay time (RT60) using Sabine’s formula and determine exact square footage of acoustic absorption panels needed.

Free Screen PPI & Pixel Density Calculator

Calculate monitor PPI, pixel pitch, and Retina viewing distance for any resolution.

Free Sound Wavelength Calculator

Compute exact sound velocity, wavelength, quarter-wave reflection boundary, and room acoustic standing wave dimensions based on air temperature.

Free Soundproofing STC & Mass-Air-Mass Calculator

Calculate Sound Transmission Class (STC), Mass-Air-Mass resonant frequency (f0), and low-frequency bass isolation across wall constructions.

Free Speaker Baffle Step Diffraction Calculator

Calculate the 6 dB acoustic baffle step transition frequency (f3), dipole rolloff, and crossover BSC compensation inductor (mH) and resistor values.

Free Speaker Crossover Calculator

Calculate passive crossover component values (capacitors in μF and inductors in mH) for 2-way loudspeaker driver integration.

Free Speaker Notch Filter Calculator

Calculate precision parallel RLC component values (R, L, C) to tame harsh driver breakup peaks and cabinet baffle step acoustic resonances.

Free Speaker Wire Gauge & Damping Factor Calculator

Calculate round-trip speaker cable resistance, power loss in dB, and effective amplifier damping factor degradation.

Free Studio Monitor Placement Calculator

Calculate the equilateral listening triangle, listener 38% room position, and wall boundary SBIR bass cancellation frequencies.

Free Subtitle Time Shifter & Sync Calculator

Calculate millisecond delay offsets and framerate drift fixes for SRT and VTT subtitles.

Free Subwoofer Box Tuning Frequency & Port Calculator

Calculate enclosure tuning frequency (Fb), port length for round or slot ports, end correction, and port chuffing limits.

Free Subwoofer Box Volume & Tuning Calculator

Calculate ported enclosure volume, port tuning length (Fb), and vent air velocity.

Free Subwoofer Box Volume Calculator

Calculate optimal sealed enclosure volume, ported box internal volume, tuning frequency (Fb), and port tube dimensions to eliminate chuffing.

Free Subwoofer Delay & Phase Alignment Calculator

Calculate acoustic latency delay (ms), physical distance offset, phase angle at crossover, and polarity inversion to stop destructive bass cancellation.

Free Subwoofer Port Air Velocity & Chuffing Calculator

Calculate peak resonant air velocity (m/s and Mach number) inside bass reflex ports to eliminate chuffing and turbulent wind noise.

Free Tape Delay & Reel-to-Reel Speed Calculator

Calculate exact echo delay times (milliseconds and tempo subdivisions) from tape speed (IPS) and record-to-playback head spacing.

Free Telescope Magnification Calculator

Calculate magnification, true field of view (TFOV), exit pupil in millimeters, and focal ratio to choose the perfect eyepiece.