ForHosting KIT
Free tools that work
right in your browser.
Calculators, converters, PDF, text, images and much more — each with its own page. Type your data and get the result right here, with no sign-up and without your data leaving your device. Need them in your own app? The same tools are available by API.
REST APILive
EmailLive
Webkit.forhosting.comLive
TelegramLive
iOS & AndroidBuilding
WhatsAppComing
7830tools
7432free in your browser
8languages
6channels
Find your tool
Search in your own words or filter by category.
🏗️ Engineering & constructionFree
Belt and pulley speed calculator
A 4-unit pulley turning at 1750 rpm drives a 10-unit pulley at 700 rpm, a ratio of 0.4. Enter the driver speed and both diameters to check a belt drive before…
B
Runs in your browser
🏗️ Engineering & constructionFree
Orbit total energy calculator
A 1000 kg satellite circling a 5.972 × 10²⁴ kg planet at 6,771,000 m from its centre has a negative total energy, which means it is bound.
K
Runs in your browser
🏗️ Engineering & constructionFree
Orbital angular momentum calculator
A satellite 7,000,000 m from the planet's centre moving at 7500 m/s along the local horizontal carries 52,500,000,000 m²/s of angular momentum per unit of its…
B
Runs in your browser
🏗️ Engineering & constructionFree
Specific orbital energy calculator
A low Earth orbit with a 6778 km semi-major axis has a specific energy of roughly minus twenty-nine million joules per kilogram, so the satellite is bound.
S
Runs in your browser
🏗️ Engineering & constructionFree
Surface gravity from density calculator
A body with a mean density of 5514 kg/m³ and a radius of 6371000 m has a surface gravity of 9.8212937284 m/s², like Earth.
A
Runs in your browser
🏗️ Engineering & constructionFree
Gravitational binding energy two masses calculator
The Earth and the Moon, 384400000 m apart, have a gravitational potential energy of −7.6130121671e28 J.
S
Runs in your browser
🏗️ Engineering & constructionFree
First-class lever calculator
On a crowbar with the fulcrum 0.5 m from a 120 N load and 2 m from your hand, a push of 30 N holds it in balance.
K
Runs in your browser
🏗️ Engineering & constructionFree
Friction for rolling without slipping
A solid cylinder on a 30° incline needs a static friction coefficient of at least about 0.19 to roll without slipping.
P
Runs in your browser
🏗️ Engineering & constructionFree
Seconds pendulum length calculator
Under standard Earth gravity of 9.80665 m/s², a pendulum that takes one second per swing and two per full cycle needs a length close to one metre.
B
Runs in your browser
🏗️ Engineering & constructionFree
SHM displacement calculator
An oscillator with a 0.5 m amplitude and an angular frequency of π rad/s, starting at its maximum, is back at equilibrium after 0.5 s.
K
Runs in your browser
🏗️ Engineering & constructionFree
SHM total energy calculator
A 200 N/m spring oscillating with a 0.1 m amplitude holds 1 J of total energy, the same at every instant of the cycle.
A
Runs in your browser
🏗️ Engineering & constructionFree
Force to Tip an Object Calculator
A block weighing 980 N with a 0.6 m base, pushed at a height of 1.2 m, starts to tip under a horizontal force of 245 N.
B
Runs in your browser
🏗️ Engineering & constructionFree
Vertical spring stretch calculator
A 2 kg mass hanging from a 100 N/m spring under 9.8 m/s² gravity stretches it by 0.196 m. Enter mass, spring constant and gravity to get the static sag and the…
S
Runs in your browser
🏗️ Engineering & constructionFree
Apparent weight in fluid calculator
A 100 N object fully under water, displacing 0.002 m³, reads 80.38 N on a scale: the calculator works out the buoyant force, 19.62 N here, and subtracts it from…
K
Runs in your browser
🏗️ Engineering & constructionFree
G-force calculator
An acceleration of 19.6133 m/s² is exactly 2 g: enter either value and get both, with the sign kept so braking and speeding up stay apart in your test data or…
K
Runs in your browser
🏗️ Engineering & constructionFree
Ladder equilibrium calculator
A 200 N ladder, 5 m long and set at 60 degrees to the floor, needs a floor friction coefficient of at least 0.288675134595 so its foot does not slide.
P
Runs in your browser
🏗️ Engineering & constructionFree
Moment of a force calculator
A 20 N push applied 0.4 m from a hinge, measured at right angles to the force, turns it with a moment of 8 N·m.
A
Runs in your browser
🏗️ Engineering & constructionFree
Pulley system effort calculator
How hard do you have to pull? With four strands holding 400 N, the ideal pull is 100 N, a quarter of the load; two strands halve it.
S
Runs in your browser
🏗️ Engineering & constructionFree
Stokes drag force calculator
A sphere of radius 0.001 m moving at 0.01 m/s through a fluid of 0.001 Pa·s feels a drag of 1.88496e-7 N.
S
Runs in your browser
🏗️ Engineering & constructionFree
Weight at latitude calculator
A 70 kg mass reads 686.4655 N at the poles and a little less toward the equator, where Earth's spin takes about 0.034 m/s² off gravity.
P
Runs in your browser
➗ MathFree
All primitive roots modulo n
Modulo 14 there are 6 invertible residues and exactly two primitive roots, 3 and 5. Enter a modulus from 2 to 10,000 to get the complete sorted list of…
B
Runs in your browser
➗ MathFree
Cipolla modular square root
Cipolla's algorithm gives the actual square root modulo an odd prime, not just a yes or no: for 2 modulo 7 it returns 3 and 4, since 3 squared is 9, which is 2…
A
Runs in your browser
➗ MathFree
Fermat's little theorem checker
Enter a base and a modulus and see whether a^(n−1) mod n equals 1: for 2 and 7 the remainder of 2^6 is 1, for 2 and 15 it is 4.
S
Runs in your browser
➗ MathFree
Hensel lifting calculator
Starting from 3, a root of x² − 2 modulo 7, Hensel lifting gives 10 modulo 49, 108 modulo 343 and 2166 modulo 2401.
B
Runs in your browser
➗ MathFree
Modular division calculator
Divide in modular arithmetic: 8 divided by 3 modulo 11 is 10, because the inverse of 3 is 4 and 3 times 10 leaves the remainder 8.
A
Runs in your browser
➗ MathFree
Pisano period calculator
Find the Pisano period for any modulus up to 1,000,000: modulo 10 the Fibonacci remainders repeat every 60 steps, and modulo 2 every 3.
K
Runs in your browser
➗ MathFree
Pocklington primality test
Proves a number prime from a partial factorization of n − 1: for 31, the primes 2, 3 and 5 of 30 give a factored part of 30, and since 900 is at least 31, one…
S
Runs in your browser
➗ MathFree
Difference of squares factorization
5959 equals 80² − 21², and that split reveals its factors 59 and 101. Enter an odd composite number and get the two squares, the closest factor pair and an…
B
Runs in your browser
➗ MathFree
Euler-Jacobi pseudoprime checker
561 is an Euler–Jacobi pseudoprime to base 2: the power with exponent 280 leaves 1, matching its Jacobi symbol, although 561 is composite.
P
Runs in your browser
➗ MathFree
Integer nth root floor calculator
The cube root of 1000 is exactly 10, while the cube root of 999 rounds down to 9. This calculator gives that whole-number floor for any root degree from 1 to…
K
Runs in your browser
➗ MathFree
Liouville function calculator
λ(12) is −1, because 12 is 2 × 2 × 3, three prime factors counted with repetition. Enter any positive integer to get 1 for an even count or −1 for an odd one…
B
Runs in your browser
➗ MathFree
Lucas primality test
29 is proven prime with base 2: 2 raised to 28 leaves 1 modulo 29, and the checks for 2 and 7, the prime factors of 28, both pass.
K
Runs in your browser
➗ MathFree
Powerful part calculator
Splits any positive whole number into its largest powerful divisor and a squarefree cofactor: 12 becomes 4 × 3, because 2 appears squared and 3 only once.
S
Runs in your browser
➗ MathFree
Prime factor count with multiplicity
Counts every prime factor of n, repeats included: 12 is 2 × 2 × 3, so Ω(12) is 3, while its distinct primes ω(12) are only 2.
A
Runs in your browser
➗ MathFree
Abundancy index calculator
The divisors of 12 add up to 28, so its abundancy index is 28/12, reduced to 7/3: above 2, which makes 12 abundant.
P
Runs in your browser
➗ MathFree
Aliquot sequence calculator
Starting at 12, the aliquot sequence runs 12, 16, 15, 9, 4, 3, 1, 0 and ends at zero after 7 steps.
B
Runs in your browser
➗ MathFree
Calkin–Wilf sequence term
Term 5 of the Calkin-Wilf sequence is 3/2, reached from the root 1/1 by one step left and one step right.
A
Runs in your browser
➗ MathFree
Continued fraction convergents
Enter the partial quotients 3, 7, 15, 1 and you get the convergents 3/1, 22/7, 333/106 and 355/113, each a closer fraction for π.
S
Runs in your browser
➗ MathFree
Deficient number checker
15 is deficient: its proper divisors 1, 3 and 5 add up to 9, which is less than 15. Enter any positive integer to get the exact divisor sum and a plain yes or…
K
Runs in your browser
➗ MathFree
Pell equation solver
Get the smallest positive solution of x² − Dy² = 1 for a non-square D: for 2 it is x 3 and y 2, and for 61 it jumps to x 1766319049 and y 226153980, exact to…
K
Runs in your browser
➗ MathFree
Proper divisors list
Lists every positive divisor of n except n itself, in ascending order with a count: for 12 you get 1, 2, 3, 4 and 6, five in all.
A
Runs in your browser
➗ MathFree
Sum of totatives
The numbers up to 10 that share no factor with 10 are 1, 3, 7 and 9, and they add up to 20. Enter a positive whole number to get that sum, its totient and its…
S
Runs in your browser
➗ MathFree
Engel Expansion Calculator for Positive Fractions
4/13 has the Engel denominators 4, 5, 7 and 13, which give 1/4 + 1/20 + 1/140 + 1/1820. Enter a positive fraction and get the exact expansion with no decimal…
B
Runs in your browser
➗ MathFree
Frobenius number for two coins
Coins of 4 and 7 can pay every amount above 17, but never 17 itself: this calculator finds that largest impossible amount for any two coprime values and counts…
P
Runs in your browser
➗ MathFree
Gaussian integer multiplication calculator
Multiply two Gaussian integers exactly: (3 + 2i)(1 − 4i) gives 11 − 10i. The calculator expands the product, replaces i² with −1 and returns the real and…
B
Runs in your browser
➗ MathFree
Odd parts partition count
Count the ways to write a number as a sum of odd parts: 10 has 10 such partitions, and by Euler's theorem that is also how many ways it splits into distinct…
K
Runs in your browser
➗ MathFree
Pythagorean triple generator
Builds a Pythagorean triple from two whole numbers m greater than n with Euclid's formula: choosing 2 for m and 1 for n gives the 3-4-5 triangle.
S
Runs in your browser
➗ MathFree
Sum of two squares checker
65 is a sum of two squares, 1² + 8², while 3 and 7 never are. Enter a whole number to get a yes or no, one working pair and the prime factors behind Fermat's…
A
Runs in your browser
➗ MathFree
Taxicab number representations as sums of two positive cubes
1729 can be written as 1³ + 12³ and as 9³ + 10³, so it has two representations. Enter a whole number to see every pair of positive cubes that adds up to it, or…
K
Runs in your browser
➗ MathFree
Woodall number generator
The fifth Woodall number is 5 × 2⁵ − 1 = 159, a number with 3 digits. Enter a positive position to get its exact Woodall number and digit count, even when the…
A
Runs in your browser
➗ MathFree
Integer compositions count
The number 5 can be written as an ordered sum in 16 ways, because the count of compositions is always 2^(n-1).
P
Runs in your browser
➗ MathFree
Digitadition generators
101 has two generators, 91 and 100, because 91 + 10 and 100 + 1 both equal 101. Enter a positive whole number to list every generator in ascending order, or…
S
Runs in your browser
➗ MathFree
Moran number checker
Check whether a number divided by its digit sum gives a prime: 18 has digit sum 9, 18 divided by 9 is 2, and 2 is prime, so 18 is a Moran number.
B
Runs in your browser
➗ MathFree
Pernicious number checker
Count the ones in a number's binary form and see whether that count is prime: 13 is 1101 in binary, with 3 ones, so it is pernicious.
K
Runs in your browser
➗ MathFree
Prime quadruplet finder
Lists every group of four primes shaped p, p + 2, p + 6, p + 8 up to your limit: the first is 5, 7, 11, 13, and a group only counts once its largest member…
B
Runs in your browser
➗ MathFree
Right-Truncatable Prime Checker
Checks whether a prime stays prime as you remove its last digit again and again: 3797 gives 379, 37 and 3, all prime, so it passes.
K
Runs in your browser
➗ MathFree
Strobogrammatic number checker
619 turned upside down still reads 619, so it is strobogrammatic, while 10 fails because the turn reverses its digits.
S
Runs in your browser
➗ MathFree
Wilson prime checker
5 is a Wilson prime: 4! + 1 = 25, which 5² divides exactly, leaving remainder 0. Enter a prime to see the exact remainder and whether this rare condition holds…
A
Runs in your browser
➗ MathFree
Digit frequency counter
In 100234001 the digit zero appears 4 times, one appears 2 times and two, three and four once each.
B
Runs in your browser
➗ MathFree
Product of digits calculator
The digits of 234 multiply to 24, because 2 × 3 × 4 = 24. Enter zero or any positive whole number and get the product of its digits in a single pass, with every…
B
Runs in your browser
No capabilities match your search.
How it works
1
Get your key
Create an account with your email and add balance when you need it. No subscription, no sales call.
2
Call the endpoint
One authenticated POST. The API returns a task_id immediately — copy-paste snippets in five languages on every page.
3
Collect the result
Receive a signed webhook the moment it's ready, or fetch a signed link. A failed task is never charged.
Pay only for what you use
No subscription. Free tools run in your browser; paid tasks draw from your balance, which never expires.
Free tools
$0.00
On-device utilities — hash, QR, JSON, Text→PDF and more — run in your browser. No account, no limits.
Pay-as-you-go
Per task
$0.002+
The full API — 7800+ capabilities — billed only for what you run, from $0.002 per call. No monthly fee.
Balance
$10.00+
Top up your balance and spend it across web, API and the app. It never expires.