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 Evaluators
Evaluate consequences of SWR & feedline losses, KD6DKS.
Attenuator
Calculators
"T" and Pi topologies using online interactive Excel OWA technology.
Attenuators
Minimum loss attenuator design.
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.
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.
Coordinate System Converter
Convert between rectangular, polar, spherical, and cylindrical coordinates.
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
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.
EIA Equipment Rack Stencils for Visio
By Kirt Blattenberger.
Electromagnetic Field Applets
Very nice graphical output and user interface, with animation.
 Electromagnetic Waves
 Circuits
 Transmission Lines
 Linear Antennas
 Signal Integrity
 EMC / EMI
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
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.
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.
HP48 Calculator Programs
Lots of engineering programs.
iCalculator
Huge collection of online calculators for tax, finance, math, engineering, mortgages,
logistics, loans, budgets, conversions, sports & health, statistics, mechanics,
and other topics.
Inflation Calculator
U.S. Bureau of Labor Statistics (BLS).
JPole
Antenna Calculator
Enter the operating frequency and calculate antenna dimensions  online.
Martindale's Calculator OnLine Center
More than 20,000 calculators  this site has grown incredibly over the years.
MegaConverter2
Multifunctional units converter.
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.
Espresso Engineering 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 & 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).
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.
Transmission Line Calculator
The CircuitCalculator.com Website
Excelbased calculator
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.
Unit Converter
This is a very extensive measurement value and units converter for length, weight,
height, area, temperature, time, pressure, speed, force, etc. Each and every converter
has a detailed explanation with an example.
Web Cool Tools
RF & microwave design applets that use numerical input or sliders for setting
parameters.
Corrugated
LowPass Filter Design Workshop
Wireline Calculator
WLAN Link Planning Calculators
Many calculators for wireless link planning: Fresnel zone, diffraction, path
loss, link budget, cable loss.
