Boost converter calculator
With 12 V in and a 0.5 duty cycle, an ideal boost converter delivers 24 V, a gain of 2. Enter input voltage and duty cycle as a fraction to get the output, gain and formula for your lab notebook. Free in your browser.
- Free
- Runs in your browser
- No sign-up
- Your data stays on your device
Run — free
Worked example
- Vin
- 12
- Duty cycle
- 0.5
- Vout
- 24
- Voltage gain
- 2
- Equation
- Vout = 12 / (1 − 0.5) = 24 V
- Unit voltage
- V
An ideal boost converter, also called a step-up DC–DC converter, raises a DC input voltage Vin to a higher DC output Vout by switching an inductor into a diode–capacitor network. In continuous conduction with lossless parts, volt-second balance on the inductor yields the textbook identity Vout equals Vin divided by one minus the switch duty cycle D. This calculator accepts a finite input voltage and a duty cycle between zero and one, then returns the stepped-up output voltage, the voltage gain one over one minus D, and a short formula string you can copy into a lab notebook. Negative input voltage is rejected because this elementary model describes a unipolar DC source feeding a step-up stage, not an AC inverter. A duty cycle of one is rejected as well: one minus D would be zero and the ideal gain would be infinite.
How the ideal boost converter formula Vout = Vin / (1 − D) arises
During the on interval of duration D times the switching period T the transistor is closed, the inductor is connected across the DC source, and inductor current ramps up under voltage Vin. During the off interval of duration (1 − D) times T the switch opens, inductor current continues through the diode into the output capacitor and load, and the inductor voltage is Vin minus Vout, which is negative once the output already exceeds the input.
In periodic steady state the net volt-seconds on the inductor over one cycle must be zero, otherwise the magnetizing current would walk away without bound. That balance is Vin times D times T plus (Vin minus Vout) times (1 − D) times T equals zero.
Cancel the common period T, expand the second term, and collect like terms: Vin times D plus Vin minus Vin times D minus Vout plus Vout times D equals zero, which simplifies to Vin equals Vout times (1 − D), hence Vout equals Vin divided by (1 − D). The voltage conversion ratio M equals Vout over Vin equals one over (1 − D) and is always at least one for duty cycle in the half-open interval from zero inclusive to one exclusive.
At D equal to zero the switch never turns on and Vout equals Vin; as D approaches one the ideal gain grows without bound. Real converters include inductor winding resistance, switch drop, diode drop, and discontinuous-conduction boundaries that reduce the voltage actually achieved, but those losses are outside this elementary identity.
Where a boost converter calculator earns its keep
Power-electronics laboratories ask students to predict the ideal output of a boost stage before they build it on a breadboard or a PWM-controlled MOSFET module; a trusted oracle that returns Vin divided by (1 − D) speeds pre-lab calculations and auto-grading of homework that would otherwise hide arithmetic slips. Renewable-energy notebooks convert a photovoltaic string voltage into the bus voltage implied by a chosen duty cycle during maximum-power-point walk-throughs, and they need honest rejection of a duty cycle of one rather than a silent infinity that poisons a spreadsheet.
Failed validation does not consume balance. Keep D away from unity in real hardware: as duty cycle approaches one, inductor current and switch stress grow, and parasitic resistance collapses the theoretical infinite gain. Use a dedicated converter-design landing for those questions so this search intent stays sharp.
What you can do with it
Power-electronics labs and homework
Predict the ideal boost output Vout = Vin / (1 − D) before a breadboard or MOSFET module lab, and auto-grade student duty-cycle calculations against a deterministic oracle.
PV and MPPT notebooks
Convert a photovoltaic string voltage and a chosen switch duty cycle into the implied DC bus voltage during maximum-power-point walk-throughs.
FAQ
What happens if the duty cycle is not between 0 and 1?
Duty cycle is the switch on-time fraction D, not a percent; values below 0 or above 1, and D exactly equal to 1 (infinite ideal gain), are rejected and are not billed.
Why is a negative input voltage rejected?
This elementary model describes a unipolar DC step-up stage.
Does the calculator include inductor, diode, and switch losses?
No. It reports only the lossless continuous-conduction identity Vout = Vin / (1 − D). Parasitic resistance, diode drop, discontinuous conduction, and efficiency belong on a converter-design landing.
Should I enter the duty cycle as 50 or 0.5?
As a fraction: 0.5 means the switch is on for half of each switching period. A value of 50 is rejected, so a percentage can never slip through as if it were a fraction.
What output do I get with a duty cycle of zero?
The output equals the input, because the switch never turns on and the gain is one. As the duty cycle approaches one the ideal gain grows without bound, which is why a duty cycle of exactly one is rejected.
Related tools
For developers — API access
Everything on this page is available programmatically. This section is for teams who want to wire it into their own systems; everyone else can just use the tool above.
API endpoint
Prefer to automate it? One authenticated POST creates the task; the result comes back by webhook or a signed link. The same capability also runs here on the web, by email and from Telegram — and soon from our app too.
Call it from your stack
curl -X POST https://api.kit.forhosting.com/phys/boost-converter \
-H "Authorization: Bearer $KIT_KEY" \
-H "Content-Type: application/json" \
-d '{"vin":12,"duty_cycle":0.5}'const res = await fetch("https://api.kit.forhosting.com/phys/boost-converter", {
method: "POST",
headers: {
"Authorization": `Bearer ${process.env.KIT_KEY}`,
"Content-Type": "application/json"
},
body: JSON.stringify({
"vin": 12,
"duty_cycle": 0.5
})
});
const { task_id } = await res.json();import os, requests
res = requests.post(
"https://api.kit.forhosting.com/phys/boost-converter",
headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
json={
"vin": 12,
"duty_cycle": 0.5
},
)
task_id = res.json()["task_id"]<?php
$res = file_get_contents("https://api.kit.forhosting.com/phys/boost-converter", false, stream_context_create([
"http" => [
"method" => "POST",
"header" => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
"content" => '{"vin":12,"duty_cycle":0.5}',
],
]));
$task = json_decode($res, true);body := bytes.NewBufferString(`{"vin":12,"duty_cycle":0.5}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/phys/boost-converter", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)Example request
{
"vin": 12,
"duty_cycle": 0.5
}Example response
{
"task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
"type": "phys.boost_converter",
"status": "queued",
"_links": {
"result": "/tasks/tsk_…/result"
}
}The API is asynchronous: the call returns a task_id immediately and the result arrives by webhook. Polling is capped at 1 req/s per task.
Pricing
Published price — no tokens, no invented credits. A failed task is never charged.
Errors
| HTTP | Code | Meaning |
|---|---|---|
401 | unauthorized | Missing or invalid API key. |
402 | insufficient_balance | Your balance doesn't cover the task price. |
404 | unknown_type | That task type doesn't exist. |
429 | rate_limited | Too many requests. Use the webhook instead of polling. |
Technical notes
How the ideal boost converter formula Vout = Vin / (1 − D) arises
The implementation is deterministic floating-point arithmetic with no network calls, no random seeds, and no wall-clock timestamps, so identical inputs always yield identical JSON.
Input contract, response shape, and error behaviour
If vin is strictly negative the task fails because a negative source voltage is outside this unipolar boost model; zero is allowed and yields zero output. Duty cycle is a fraction, not a percent: D equals 0.5 means fifty percent on-time, and a value of 50 is rejected. Send two required finite numbers: vin, the DC input voltage in volts, and duty_cycle, the switch on-time fraction D. Aliases are accepted: v_in, input_voltage, and Vin for the source; duty, d, and D for the duty cycle. Each field may arrive as a JSON number or as a numeric string. Missing fields, empty strings, NaN, and Infinity fail with invalid_input naming the field. If duty_cycle is not between 0 and 1 — that is, D less than zero or D greater than one — the task fails with a message that the duty cycle must be between 0 and 1. If D is exactly 1, one minus D is zero and the ideal output is undefined, so that case is also invalid_input rather than Infinity. On success the body echoes cleaned vin and duty_cycle, returns vout equal to vin divided by (1 − duty_cycle) rounded to twelve decimal places for stable goldens across runtimes, voltage_gain equal to one over (1 − D), unit_voltage V, plus formula and equation strings for worksheets. Example: vin equals twelve volts and duty_cycle equals one half yields vout of twenty-four volts and a gain of two, because twelve divided by (1 − 0.5) is twenty-four. Pricing for successful API calls is the published base of $0.002 per item; validation failures do not consume prepaid balance. Pair the free browser form with the same module the API uses so classroom demos and automated tests never diverge.
Where a boost converter calculator earns its keep
This endpoint reports only the ideal continuous-conduction identity; it does not size the inductor, choose the switching frequency, or model discontinuous conduction, ripple, or efficiency.
Integration use cases
Firmware tests for boost rails
Assert the expected bus voltage of a LED driver, USB-C boost, or battery-to-12 V converter in unit tests without standing up a SPICE deck for every firmware revision.
Technical questions
How do I compute the output voltage of an ideal boost converter?
Send finite numbers vin (non-negative DC input in volts) and duty_cycle D with 0 ≤ D < 1. The API returns Vout = Vin / (1 − D) and the voltage gain 1/(1 − D).
What does the boost converter calculator cost?
The browser tool is free. API requests use prepaid KIT balance at $0.002 per successful call; invalid input is not billed.