Electric charge converter
One coulomb is 1000 millicoulombs. Convert charge between coulombs, millicoulombs, microcoulombs, ampere-hours, milliampere-hours and elementary charges, so battery labels, capacitor notes and particle estimates share one exact scale. Free in your browser.
- Free
- Runs in your browser
- No sign-up
- Your data stays on your device
Run — free
Worked example
- Value
- 1
- Source unit of 'value'
- C
- To
- mC
- Result
- 1,000
- From label
- coulomb
- To label
- millicoulomb
- Value C
- 1
This electric charge converter turns a numeric charge from one common unit into another and returns the converted magnitude with canonical unit labels. Conversion always bridges through the coulomb using fixed SI factors, including the exact elementary charge constant, so the same input always yields the same result with no network calls, no sampling, and no date-dependent shortcuts. Typical checks include one coulomb to millicoulombs, two ampere-hours to coulombs, and two thousand milliampere-hours to ampere-hours.
What the electric charge converter returns and which units it understands
A charge conversion answers a narrow question: given a magnitude in one charge-family unit, what is the equivalent magnitude in another unit that people actually print on battery labels, capacitor notes, particle-physics estimates, and lab worksheets. This calculator accepts a numeric value, a source unit, and a target unit, then returns the converted result rounded to a stable precision, the canonical from and to identifiers, human-readable labels, the intermediate value in coulombs, and the SI factors used for the bridge.
Canonical ids are C for coulomb, mC for millicoulomb, uC for microcoulomb, Ah for ampere-hour, mAh for milliampere-hour, and e for the elementary charge. Everyday spellings such as coulombs, millicoulombs, microcoulombs, ampere-hours, milliampere-hours, µC, μC, amp hour, and elementary charge normalize to those ids so forms, query strings, and spreadsheets can reuse the same contract without inventing private enums.
Where charge conversion fits in batteries, labs, and software
Battery and power-electronics work often mixes milliampere-hour pack labels with ampere-hour nameplates and coulomb-based coulomb-counting firmware on the same design, while capacitor notes and electrostatics labs quote microcoulombs and particle or nuclear estimates use elementary charges, so a single deterministic converter prevents hand-calculator drift when an engineer, technician, or student compares values.
Lab reports convert measured coulombs into the unit the rubric expects; procurement tools map supplier capacity strings into a single SI magnitude before stocking; teachers assign homework that needs a fast, offline check of SI prefixes and ampere-hour factors without trusting opaque apps that silently change precision. Developers call the same contract from scripts to seed deterministic test vectors for product UIs, to normalize user-entered battery capacities before sizing demos, or to satisfy programming-challenge statements that demand exact SI factors rather than a hand-waved estimate.
Product tools use the rewrite when a learner or agent types two thousand milliampere-hours and the UI must show ampere-hours and coulombs side by side. Pair it with electric potential or power tools when you need related circuit quantities first, and with the general multi-category unit converter when the same form must also handle length or mass.
What you can do with it
Battery capacity labels
Convert between milliampere-hours, ampere-hours, and coulombs when comparing pack ratings, datasheets, and coulomb-counting firmware.
Lab electrostatics and capacitors
Map millicoulombs and microcoulombs into coulombs for lab reports, homework checks, and deterministic equipment logs.
FAQ
What does the electric charge converter cost?
It is free in your browser on this page.
What happens if I send an unknown unit?
Unknown or misspelled units are never silently mapped.
Does this compute capacitance or current as well?
No. This capability converts electric charge units only. For capacitance (Q=CV), current from charge and time, or electric potential, use the dedicated tools for those quantities.
How many coulombs are in one ampere-hour?
Exactly 3600. An ampere is one coulomb per second and an hour has 3600 seconds, so one ampere-hour is 3600 coulombs and one milliampere-hour is 3.6 coulombs.
How do I convert mAh to Ah?
Divide by 1000, since a milliampere-hour is a thousandth of an ampere-hour. A battery labelled 2000 mAh therefore holds 2 Ah, which makes pack labels and nameplates easy to compare.
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/conv/electric-charge \
-H "Authorization: Bearer $KIT_KEY" \
-H "Content-Type: application/json" \
-d '{"value":1,"from":"C","to":"mC"}'const res = await fetch("https://api.kit.forhosting.com/conv/electric-charge", {
method: "POST",
headers: {
"Authorization": `Bearer ${process.env.KIT_KEY}`,
"Content-Type": "application/json"
},
body: JSON.stringify({
"value": 1,
"from": "C",
"to": "mC"
})
});
const { task_id } = await res.json();import os, requests
res = requests.post(
"https://api.kit.forhosting.com/conv/electric-charge",
headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
json={
"value": 1,
"from": "C",
"to": "mC"
},
)
task_id = res.json()["task_id"]<?php
$res = file_get_contents("https://api.kit.forhosting.com/conv/electric-charge", false, stream_context_create([
"http" => [
"method" => "POST",
"header" => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
"content" => '{"value":1,"from":"C","to":"mC"}',
],
]));
$task = json_decode($res, true);body := bytes.NewBufferString(`{"value":1,"from":"C","to":"mC"}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/conv/electric-charge", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)Example request
{
"value": 1,
"from": "C",
"to": "mC"
}Example response
{
"task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
"type": "conv.electric_charge",
"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.
Limits
max_abs_value | 1000000000000000000 |
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
Supported units are coulombs, millicoulombs, microcoulombs, ampere-hours, milliampere-hours, and elementary charges, plus everyday aliases such as C, mC, µC, μC, Ah, mAh, coulomb, millicoulomb, microcoulomb, ampere-hour, and elementary charge.
What the electric charge converter returns and which units it understands
There is no approximate material model and no capacitance or current path: the engine either multiplies and divides by fixed factors inside the supported magnitude range or rejects the input with invalid_input. Rejected cases include missing value, from, or to; non-finite numbers; magnitudes above the documented ceiling; and any unit string that is not on the supported list.
How factors are defined and how results stay reproducible
Optional scientific notation on the value string is allowed when it parses as a finite decimal; embedded spaces, hex prefixes, and non-numeric tokens are rejected with a clear message so a bad cell does not become a wrong capacity entry. Zero is a valid value and simply yields zero in the target unit. Computation multiplies value by the source factor in coulombs, then divides by the target factor: one millicoulomb is exactly one thousandth of a coulomb; one microcoulomb is exactly one millionth of a coulomb; one ampere-hour is exactly three thousand six hundred coulombs because an ampere is one coulomb per second and an hour is three thousand six hundred seconds; one milliampere-hour is exactly three point six coulombs; one elementary charge is exactly one point six zero two one seven six six three four times ten to the minus nineteen coulombs by the SI definition since twenty nineteen. The preferred fields are value for the charge magnitude, from for the source unit, and to for the target unit, with aliases amount, charge, q, and quantity for the value, unit, from_unit, source, and input_unit for from, and target, to_unit, output_unit, and into for to so heterogeneous clients can share one contract. An optional precision field, with aliases decimals and dp, chooses how many decimal places to expose for value, result, and value_C, defaulting to ten and capped at fifteen so JSON goldens stay stable. Pair the free browser run on this page with the priced API when you need the identical mathematical result inside an automated pipeline without re-implementing unit tables yourself.
Where charge conversion fits in batteries, labs, and software
On this page the work runs entirely in your browser; through the API each successful lookup costs $0.002, failed validation is not charged, and nothing is stored after the response returns. That split — free interactive exploration and a priced, identical API — matches the rest of the KIT tier-A catalog and lets you move from a classroom demo to an automated pipeline without changing the mathematical result.
Integration use cases
Homework and CI fixtures
Generate reproducible charge conversions for worksheets, tutoring software, and unit tests that assert fixed SI and elementary-charge factors.
Technical questions
Which electric charge units are supported?
Coulomb (C), millicoulomb (mC), microcoulomb (uC, µC, μC), ampere-hour (Ah), milliampere-hour (mAh), and elementary charge (e), including common aliases such as coulombs, ampere-hours, and elementary charge.
How are conversion factors defined?
All conversions bridge through coulombs: 1 mC = 0.001 C, 1 uC = 1e-6 C, 1 Ah = 3600 C, 1 mAh = 3.6 C, and 1 e = 1.602176634e-19 C (exact SI elementary charge).