Developer Utilities
Small developer utilities that save a trip to a random website. Encode and decode Base64, explain a regex, build UTM links, generate QR codes and vCards, and more — the everyday helpers. Free in your browser, and available by API when you need them in a script.
Developer Utilities
Frequency period converter
T = 1/f and f = 1/T, free
POST /elec/frequency-period$0.002Developer Utilities
Inductive reactance calculator
XL = 2πfL in ohms, free
POST /elec/inductive-reactance$0.002Developer Utilities
LC resonant frequency calculator
f₀ = 1/(2π√(LC)), free
POST /elec/lc-resonant-frequency$0.002Developer Utilities
LED resistor calculator
series resistor and power rating
POST /elec/led-resistor$0.002Developer Utilities
Magnetic field of a straight wire calculator
B = μ₀I/(2πr), free
POST /elec/magnetic-field-wire$0.002Developer Utilities
Magnetic force calculator
Lorentz F=qvB sinθ on a moving charge, free
POST /elec/magnetic-force-charge$0.002Developer Utilities
Force on a current-carrying wire calculator
F = I L B sin(θ)
POST /elec/magnetic-force-wire$0.002Developer Utilities
555 timer calculator
astable frequency and duty cycle
POST /elec/ne555-astable$0.002Developer Utilities
555 timer monostable calculator
pulse width t=1.1RC, free
POST /elec/ne555-monostable$0.002Developer Utilities
Non-inverting amplifier calculator
gain Av = 1 + Rf/Rg, free
POST /elec/op-amp-noninverting$0.002Developer Utilities
Parallel-plate capacitor calculator
C from area, gap and dielectric
POST /elec/parallel-plate-capacitance$0.002Developer Utilities
Power gain dB calculator
G = 10·log10(Pout/Pin) from input and output power, free
POST /elec/power-gain-db$0.002Developer Utilities
PWM duty cycle calculator
on-time, period, average voltage, free
POST /elec/pwm-duty-cycle$0.002Developer Utilities
RC filter cutoff calculator
fc = 1/(2πRC) for LP/HP filters
POST /elec/rc-filter-cutoff$0.002Developer Utilities
RC time constant calculator
τ=RC and 5τ settling time, free
POST /elec/rc-time-constant$0.002Developer Utilities
Wire resistance calculator
R = ρL/A from resistivity, free
POST /elec/resistivity$0.002Developer Utilities
Series resistance calculator
total ohms for resistors in series, free
POST /elec/resistors-series$0.002Developer Utilities
RL filter cutoff calculator
fc=R/(2πL) in hertz, free
POST /elec/rl-filter-cutoff$0.002Developer Utilities
RL time constant calculator
τ = L/R for series RL circuits
POST /elec/rl-time-constant$0.002Developer Utilities
Slew rate from full-power bandwidth
SR=2πfVpeak op-amp calculator, free
POST /elec/slew-rate-bandwidth$0.002Developer Utilities
Johnson noise calculator
RMS thermal noise voltage √(4kTRΔf), free
POST /elec/thermal-noise$0.002Developer Utilities
Voltage drop calculator
AWG wire, length, current, free
POST /elec/voltage-drop-wire$0.002Developer Utilities
Voltage gain dB calculator
Av = 20·log10(Vout/Vin)
POST /elec/voltage-gain-db$0.002Developer Utilities
Watts to dBm calculator
convert power in W or mW to dBm, free
POST /elec/watts-to-dbm$0.002Developer Utilities
Watts, volts & amps calculator
solve power, voltage or current
POST /elec/watts-volts-amps$0.002Developer Utilities
Frequency to wavelength calculator
free-space RF λ = c/f, free
POST /elec/wavelength-frequency-rf$0.002Developer Utilities
Wheatstone bridge calculator
find unknown resistance Rx, free
POST /elec/wheatstone-bridge$0.002Developer Utilities
Zener diode resistor calculator
series resistor value and power rating, free
POST /elec/zener-resistor$0.002Developer Utilities
Affine cipher
encrypt or decrypt with keys a and b, free
POST /enc/affine$0.002Developer Utilities
ASCII code lookup
character to decimal, hex and octal, free
POST /enc/ascii-lookup$0.002Developer Utilities
Atbash cipher
mirror the alphabet (A↔Z), free online
POST /enc/atbash$0.002Developer Utilities
Autokey cipher
encrypt or decrypt text with a keyword extended by the message, free
POST /enc/autokey$0.002Developer Utilities
Base16 RFC 4648 encoder & decoder
uppercase hex, free
POST /enc/base16-rfc4648$0.002Developer Utilities
Base32 encoder & decoder
RFC 4648 A-Z and 2-7, free
POST /enc/base32$0.002Developer Utilities
Base58 encoder & decoder
Bitcoin alphabet, free online
POST /enc/base58$0.002Developer Utilities
Flickr Base58 encoder & decoder
short URL alphabet, free
POST /enc/base58-flickr$0.002Developer Utilities
Text to Base64
encode or decode with standard padding, free
POST /enc/base64$0.002Developer Utilities
Ascii85 / Base85 encoder
encode or decode text, free
POST /enc/base85$0.002Developer Utilities
Beaufort cipher
encrypt or decrypt text with a keyword, free
POST /enc/beaufort$0.002Developer Utilities
Bifid cipher
encrypt or decrypt text with Polybius fractionation and a keyword, free
POST /enc/bifid$0.002Developer Utilities
Text to binary converter
8-bit encode & decode, free
POST /enc/binary-text$0.002Developer Utilities
Braille translator
text to Unicode Braille (Grade 1) and back, free
POST /enc/braille$0.002Developer Utilities
Caesar cipher
encrypt or decrypt text with a letter shift, free
POST /enc/caesar$0.002Developer Utilities
Gronsfeld cipher
encrypt & decrypt with a numeric key, free
POST /enc/gronsfeld$0.002Developer Utilities
Text to hex converter
encode or decode UTF-8 bytes, free
POST /enc/hex-text$0.002Developer Utilities
Keyboard shift cipher
QWERTY adjacent-key encrypt or decrypt, free
POST /enc/keyboard-shift$0.002Developer Utilities
Leetspeak translator
convert text to 1337 speak and back, free
POST /enc/leetspeak$0.002Developer Utilities
Multiplicative cipher
encrypt & decrypt with a coprime key, free
POST /enc/multiplicative$0.002Developer Utilities
NATO phonetic alphabet
spell or decode Alpha Bravo Charlie, free
POST /enc/nato$0.002Developer Utilities
Nihilist cipher
encrypt or decrypt with Polybius square keyword and numeric key, free
POST /enc/nihilist$0.002Developer Utilities
Text to octal converter
encode UTF-8 bytes as base-8, free
POST /enc/octal-text$0.002Developer Utilities
Playfair cipher
encrypt & decrypt with a keyword square, free
POST /enc/playfair$0.002Developer Utilities
Polybius square cipher
encrypt or decrypt letters as row-column digit pairs, free
POST /enc/polybius$0.002Developer Utilities
Punycode converter
encode Unicode domains to xn--, free
POST /enc/punycode$0.002Developer Utilities
Rail fence cipher
encrypt or decrypt zigzag transposition, free
POST /enc/rail-fence$0.002Developer Utilities
ROT13 encoder
rotate letters by 13, free online
POST /enc/rot13$0.002Developer Utilities
ROT18 cipher
ROT13 letters + ROT5 digits, free online
POST /enc/rot18$0.002Developer Utilities
ROT5 digit cipher
rotate 0–9 by five, free online
POST /enc/rot5$0.002Developer Utilities
Tap code translator
Polybius encode & decode, free
POST /enc/tap-code$0.002Developer Utilities
Trifid cipher
encrypt or decrypt with a 27-symbol cube, free
POST /enc/trifid$0.002