These calculators are offered free of charge
 some by vendors and others by individuals. Some are standalone and others function
online via Java from the web page. The majority are engineering calculators, but
some are scientific calculators, some are amateur radio calculators, and some are
electrician type calculators.
See also the RF Cafe
Online Calculators and vintage
Cardboard Slide
Rule Calculators.
A good way to find on this page what you need is do
a browser page search.
AccelWare Unit Conversion
Tool  powerful, intuitive, and easytouse utility for quick and accurate conversion
between almost every possible unit of measure, from one system to another. The latest
version includes more than 2200 units in 78 categories. The categories include:
length, area, speed, mass, numbers, volume, time, density, force, pressure, energy,
power, flow, temperature, angle, light, fractions, data transfer, and many more.
Fully functional Online version now available.
All About Circuits
This is a nice assortment (83 at this time) of electrical &
electronics parameter calculators, with a couple mechanical types as well. There
are many types of substrate impedance and line dimension calculators, and calculators
for voltage dividers, inductance and capacitance, coax lines and waveguides, amplifiers,
impedance matching, free space loss, EIRP, radar range, and noise figure.
AlphiMAX P2P Signal Propagation
Calculator A very nice graphical interface tools that enables you
to compare manufacturers, while taking into account the terrain of your area, terrain
type, climate, antenna type, define fade margin and more. Use of a GPS database
produces a very accurate elevation profile between antenna locations.
Analog Devices Calculators
Big list of online calculators
Antenna System Evaluator
Evaluate consequences of SWR & feedline losses, KD6DKS.
ATC TechSelect
Capacitor Calculation, American Technical Ceramics.
Attenuator Calculators
"T" and Pi topologies using online interactive Excel OWA technology.
Attenuator Calculator Four topologies:
"T", Pi, BridgedT, Reflection.
Attenuator Calculator DK1RM Here is a JavaScript
version for Pi and T attenuators  auf Deutsch.
Attenuators Minimum loss attenuator design.
Besser Associates
4159493300 / Los Altos, CA
Broadcast Engineering Related Calculators Allen's
Broadcast Engineering Extravaganza Lots of good JavaScript calculators: AM Common
Point / Antenna Current Calculator, FM Transmitter Power Output Calculator, RPU/STL
Transmitter Frequency Tolerance Calculator, AM Transmitter Harmonics Calculator,
Free Space Loss Between Isotropic Radiators Calculator, 0.6 First Fresnel Radius
Zone Calculator, VSWR Calculator, Coaxial Cable Loss Calculator, Coax Cable Loss/Antenna
Gain Calculator, Opamp Gain Calculator
Cable Performance
Calculators Calculate loss & power, VSWR & return loss,
by Times Microwave.
Calc101 By webMathematica,
scores of online interactive calculators for algebra, trigonometry, calculus, matricies,
linear equations.
Calculator Edge
This has to be one of the Web's largest collection of unique (as opposed to copied)
online calculators. Each of these topics has many calculators within them. General,
Civil Engineering, Optical Engineering, Mechanical Engineering, Plastics Engineering,
Metallurgy, Electronics Engineering, Electrical Engineering, Chemical Engineering,
Physics, Ceramics, Oil & Gas, Structural Engineering.
CapCAD Capacitor
calculation, by Dielectric Laboratories.
Chemandy Electronics +62 31 8914627 / Jawa Timur,
Indonesia Large selection of online interactive calculators for RF design, including
attenuators, capacitance, resonance, RF traps, and microstrip impedance. Design,
development and small scale manufacture of simple RF and Audio items. We also have
the capability for ATE programming in Labview, HP/Agilent Vee or Visual Basic, and
can produce associated test jigs.
Chemistry Calculators
Boyle's Law, Charles' Law, STP, molar volume, etc, by 1728 Software Systems.
Choke Designer Inductor values using standard cores.
Coordinate System Converter Convert between rectangular,
polar, spherical, and cylindrical coordinates.
Connect802 Antenna
System Designer An online calculator that creates a wireless network
antenna system design report based on various parameters that you provide. It will
help you predict endtoend performance and evaluate your network design when you
plan a pointtopoint, or pointtomultipoint outdoor wireless network deployment.
You'll be able to analyze the radio link and tune network parameters for optimal
link suitability.
ConvertIt Huge collection
of converters and calculators.
Daycounter, Inc. Engineering
Services Calculators for switching power supply, air core inductors,
SallenKey LP Butterworth filter, L matching network, standard resistor value, PI &
T pad attenuator, reactance, series  parallel impedance conversion, ZSY parameter
conversion, Rollet Stability (K) Factor, complete RF amplifier design & analysis,
LC resonance.
Dielectric Constant of Water (Complex) Calculates
the real and imaginary parts of the dielectric constant for water, sung temperature,
salinity, and frequency. By Gareth Harris
Dirac Delta "Science and engineering encyclopedia."
Hundreds of JavaScript calculators, definitions, historical information, etc.
eeWeb
Advanced features including support for complex numbers, unit conversion, base conversion,
and has a built in equation solver. eCalc is one of the best calculators on the
web and runs completely in your browser without requiring any special plugins. Electrical
engineers will find eCalc's complex math especially useful since it supports both
rectangular and polar formats. eCalc supports both RPN and Algebraic Input Modes.
engApplets Java
applets for engineering education.
Engineering Calculators on Educypedia A pretty good
collection of links to online calculators  satellites, attenuators, Smith Chart,
VSWR, free space loss, etc.
EIA Equipment Rack Stencils for Visio By Kirt
Blattenberger.
EIA Tube Bases for Visio
Electromagnetic Field Applets Very nice graphical output
and user interface, with animation. 
Wave Propagation 
Field Polarization 
Oblique Incidence

Oblique Incidence on Lossy Medium 
Parallel Plate Waveguide 
Rectangular Waveguide 
Dielectric Slab Waveguide
everything RF
A nice collection of RF calculators. 
Attenuator Calculator 
Microstrip Impedance Calculator 
Coax Impedance
Calculator 
Cascaded Noise Figure Calculator 
Skin Depth Calculator 
Wavelength Calculator 
dBm to Watt Calculator
 Watt
to dBm Calculator
Excalibur RPN Calculator Applet Excalibur does not
use more conventional "algebraic" notation like many lowend calculators on the
market. Instead it uses the highpowered parenthesisfree RPN notation (Reverse
Polish Notation).
Fast Fourier Transform Calculator Do an FFT by entering
the time domain data in the Time Domain Data box with each sample on a new line.
For complex (I and Q) data, the real and imaginary components should be on the same
line separated by a comma. Do an Inverse FFT by entering the frequency domain data
in the Frequency Domain Data box with each sample on a new line. For complex (I
and Q) data, the real and imaginary components should be on the same line separated
by a comma.
Field Strength Calculator Enter frequency and antenna
gain, then any one of received power, electric field strength, magnetic field strength,
or power density and this calculates the others.
Filter Coupling Matrix Calculator
Facilitates synthesis of N+2 coupling matrices for Chebyshev bandpass filtering
functions, with arbitrary finiteposition transmission zeroes.
Filter Design Spreadsheets
Waveguide Filter Designer
Combline and
Interdigital Filter Design Spreadsheet
RF Shop
Financial & Mortgage
Calculators Over 100 personal finance calculators.
Financial Calculators
Loan amortization, interest, loan payment by 1728 Software Systems.
FM Antenna Calculator by ERI (Electronics Research,
Inc.) Plots FCC 60 dBu contours right on the page. Also many PDF files with Engineering
Tables: Geotechnical Investigations for Antenna Support Structures, Classes of FM
Stations, FM Broadcast Channels, AM Tower Heights by Frequency, 54 dBu Contour Distances,
60 dBu Contour Distances, Site Plot Plan, Wind Speed Map, Ice Probability Map, Antenna
Support Structure Design Radius of Curvature Requirement.
FreeSpace Loss
Calculator
Fresnel Clearance Zone
EIRP
Distance between two
points using Latitudes and Longitudes
Flex Analysis
Evaluate thermal/mechanical performance of flex circuits by Rogers Corporation.
Frequency Finder
 Open TV Channel Applet Sennheiser searches the FCC database for
an open channel for running interferencefree wireless systems.
Fresnel Clearance Zone Calculator By TeraBeam
Fresnel Zone Calculator The calculator will generate
the radius of the first Fresnel zone only (at the obstacle point or the midpoint),
the 60% (no obstacle) radius and the height of the earth curvature at the midpoint
of the Total link distance. By Wireless Connections.
Good Calculators
Large collection of calculators for engineering, finance, logistics, loans, budgets,
conversions, sports & health, statistics, mechanics, and other topics.
HiDigit
Scientific calculator with extended capabilities. Advantages include a simple input
format even for the most complicated scientific formulas; i.e., enter "10pi" instead
of "10*pi" or complex numbers as "1+2i".
HP48 Calculator
Programs Lots of engineering programs.
Impedance Matching Network Designer John Wetherell,
Berkeley, CA.
Inflation Calculator
U.S., Canadian, and Italian versions. Enter begin and end dates and get equivalent
dollar values, by S. Morgan Friedman.
Inflation
Calculator U.S. Bureau of Labor Statistics (BLS).
JPole Antenna Calculator
Enter the operating frequency and calculate antenna dimensions  online.
Julian Date Calculator
Calculates JDs for a given month.
Link Budget Calculator A towertotower, overtheair
JavaScript calculator, by Wireless Connections.
LOGInterMod
Leslie Green / U.K.  A Windows program (Freeware) that calculates twotone intermodulation
products up to the 30th order.
Martindale's Calculator OnLine Center More than
20,000 calculators  this site has grown incredibly over the years.
MegaConverter2
Multifunctional units converter.
Microwave Impedance
Calculator (MWIJ 1.0) Substrate line impedance calculator by Rogers
Corporation. Written in Java  nice.
Mortgage Calculators
Large variety of financial calculators for mortgages, principal calculation, cost
per thousand, affordability, income requirements, FHA, refinance, HELOC, loan comparison
tools, points, rent vs buy, & more.
Mortgage Calculator
8 different calculators: Mortgage calculator, Affordability, Early PayOff, Interest
Only, Advanced Mortgage calculator, Mortgage Refinance, Basic Amortization, and
Comparison calculator
N Calculators
Electronic circuit design calculators can assist you to solve, analyze and determine
the circuit design with capacitors, inductors, resistors, diodes, transistors, etc.
Many other types of financial, mathematical, and science calculators.
Noise Figure <>
Noise Temperature Calculator
Online Conversion
Convert just about anything to just about anything else.
PCB Trace & Via Calculator
A very complete set of online calculators for microstrip, embedded, and differential
microstrip impedance; stripline and differential stripline impedance; stripline
and microstrip crosstalk; currentcarrying capacity of traces and thermal vias;
heat dissipation of thermal vias. By Sören Nilsson.
PLL Phase Noise Calculator By Hittite Microwave
(now Analog Devices).
Poles &
Zeros Calculator Move the poles and zeros to see the frequency
domain response.
Power Calculator
Motor & line calculations, conversions.
Radio Calculators
Pi attenuators and air inductor java calculators by Jim Hawkins.
Random Science
Tools and Calculators The intention of this site is to produce scientific
tools and calculators, and store information which will be useful to scientists,
engineers, students and enthusiasts.
Chemistry
Electronics
Math
Physics
Resistor Color Code Calculator (Reversible) This
resistor color code calculator also provides a table of nearest standard values
of resistors for standard tolerances.
Resistor Ratio Calculator
Leslie Green / U.K. A resistive network calculator for problems using two or
three fixed resistors. You have to use standard values, but you need some silly
ratio like 3.245 V from a 10 V source. This program helps you to pick the optimum
resistor values for simple resistor dividers or opamps (inverting and noninverting).
Freeware.
RF Cafe Calculator Workbook Collection of commonly used
calculators including Attenuators, Bandpass Filters, Cascaded Components, Coils
/ Inductors, DeltaWye (Resistors), Directional Couplers, Doppler Shift, Highpass
Filters, Lowpass Filters, Mixer Frequency Conversion, Near / Far Field, Noise FigureTemp,
Path Loss, 1Way, Path Loss, 2Way, Propagation Time, Radar Blind Speed, Radar Horizon
/ Line of Sight, Rectangular Cavity, Skin Depth, Smith Chart, VSWRRLGamma, Voltage
Divider, Voltages & Power  Vrms, Vavg, Vpk
RF Cafe Online
Calculators Many online calculators for noise figure/temperature,
filter responses, voltage dividers, waveguide cutoff frequency, VSWRreturn lossreflection
coefficient conversions and more, by Kirt Blattenberger.
RF Calc
General purpose engineering calculator by MilMega  includes table of physical constants,
component parameter calculators (capacitance, inductance, resonance, pads), multiple
transmission line calculators.
RF & Analog Tutorials w/Java Apps
Website This is a VERY nice collection of Java applets and some
PDF format tutorials. Antenna patterns, waveguide modes, electromagnetic wave fronts,
interactive Smith chart, transmission lines, standing waves, resonant circuits,
radiation of wires, crosstalk, much more. By Amanogawa.
RF Cascade Workbook 2018 RF, system, cascade
for Excel spreadsheet.
RF Workbench RF, system, up/downconverter, spurious analysis,
budget  best value out there.
RPN Calculator
This handy Reverse
Polish Notation calculator was written by the infamous Kelly Painter. Note the logo
in the upper right corner (hover your cursor over it).
SatelliteRelated Calculators
Sun interference, powertonoise, tilt angle, antenna gain and more than thirty
other calculators.
Satellite Link Budget Calculator
Uplink/downlink calculator, Satellite Signals site.
Signals & Noise
Java applet for exploring random processes.
Smith Chart for Visio
By Kirt Blattenberger.
Sunshine Design Engineering
Services Ramona, CA Design specialties  hardware, CAD and software
engineering. Test Engineering Services  20 years experience RF/Microwave and Semiconductor
Parametric Test. Electronic Calculator  Multiple pages of calculators for capacitance,
resistance, inductance, attenuation, microstrip, resonance, etc. Many astronomical
calculators.
SWR Calculator
VNA Help  for microwave network analyzers.
Transmission Line Calculator The CircuitCalculator.com
Website Excelbased calculator
TRL / LRL Calculator TRL (Through, Reflect, Line)
and LRL (Line, Reflect, Line) reference plane calculators provided by ElectroPhotonics.
TXLine
Transmission Line Calculator by Applied Wave Research. This file seems to be no
longer available on the AWR website.
Ultra Converter I
Ultra Converter II
If these to converters don't have it, you don't need to convert it! by 1728 Software.
Vertex 42  Engineering
calculators & converter applets & spreadsheets.
Voltage Divider Resistor Calculator Table of tworesistor
voltage dividers using standard 5% tolerance resistor. Opamp feedbackinput resistor
pairs can also be specified. Very clever cell shading scheme for indicating deviation
from exact ratio that is specified. Provided by Mark Rushakoff.
VSWR, Power Converter, Inductance Calculator 97236175082
/ Israel Free downloadable VSWR, power converter, inductance calculator, written
by Dr. Ronen Holtzman for Elisra Microwave Division engineers.
Waveguide Filter Dimension and
Electrical Response Calculator By Guided Wave Technology.
Waveguide Applets Very nice graphical output and user interface,
with animation.
Web Cool Tools RF & microwave design applets
that use numerical input or sliders for setting parameters.
WRConnect
Waveguide structure design tool.
Corrugated LowPass
Filter Design Workshop
Waveguide & EM Calculators
This is a very nice Java/JavaScriptbased set of calculators with a great user interface.
Wireline Calculator
WLAN Link Planning
Calculators Many calculators for wireless link planning: Fresnel
zone, diffraction, path loss, link budget, cable loss.
Yagi Java Applet Change frequency, element diameter,
and number of segments.
