Acoustic impedance converter
1.5 MRayl, the figure often quoted for soft tissue, is 1,500,000 rayls. The converter moves acoustic impedance between seven units, from cgs rayls to Pa·s/m, for ultrasound datasheets, sonar reports and homework. Free in your browser.
- Free
- Runs in your browser
- No sign-up
- Your data stays on your device
Run — free
Worked example
- Value
- 1.5
- From
- MRayl
- To
- Rayl
- Result
- 1,500,000
- From label
- megarayl (MRayl)
- To label
- rayl (MKS)
- Pa s m
- 1,500,000
An acoustic impedance converter turns a characteristic impedance written in one acoustics unit into another without hunting tables for rayls, cgs rayls, or pascal-seconds per metre.
Supported units and how acoustic impedance conversion is computed
By definition one MKS rayl equals one pascal-second per metre, which also equals one newton-second per cubic metre and one kilogram per square metre per second; those four labels share magnitude one in the intermediate base. One cgs rayl equals one dyne-second per cubic centimetre, and the exact SI relation is ten pascal-seconds per metre because one pascal is ten dyne per square centimetre and one metre is one hundred centimetres, so the ratio is exactly ten.
One megarayl is exactly one million MKS rayls, the scale often quoted for soft tissue near one point five megarayl. Because the intermediate is always Pa·s/m, converting A to B and B to A is consistent up to the published rounding of twelve decimal places, and there is no pairwise matrix that can drift out of sync.
Characteristic impedance of a medium is Z equals density times sound speed, but density-speed products and reflection-coefficient solvers are intentionally out of scope so laboratory and design users get pure unit conversion under one clear SI convention.
Where it fits in everyday acoustics work
Use the free in-browser acoustic impedance converter when you need a quick megarayls-to-rayls, cgs-rayls-to-Pa·s/m, or dyn·s/cm³-to-N·s/m³ check while reading an ultrasound textbook, transducer datasheet, underwater-acoustics report, or homework problem. Open the page, enter the number and units, and copy the result without installing a spreadsheet, a unit library, or a desktop calculator pack. Source inputs follow the same retention rules as other KIT parse items, and results are safe to cache because the algorithm is fully deterministic.
Authors shipping mobile apps or chatbots can map the result and formula fields directly into cards that show both the number and the conversion path students, clinicians, and acoustics engineers expect on paper.
What you can do with it
Medical ultrasound and tissue tables
Convert soft-tissue and probe matching layers between MRayl and Pa·s/m so textbook values, scanner settings, and research APIs stay consistent without hand-written rayl factors.
Sonar and underwater acoustics
Normalize seawater and material impedance from cgs rayls or dyn·s/cm³ into MKS rayls for SI design sheets, hydrophone notes, and simulation inputs.
FAQ
What is the difference between a rayl and a cgs rayl?
One MKS rayl equals 1 Pa·s/m. One cgs rayl equals 1 dyn·s/cm³, which is exactly 10 Pa·s/m.
What happens if I send an unknown unit?
The message names the field and lists supported units. Validation failures are not charged.
Is the acoustic impedance converter free?
The browser tool runs free on your device.
How many rayls are in one megarayl?
One megarayl is exactly 1,000,000 MKS rayls. So the 1.5 MRayl often given for soft tissue becomes 1,500,000 rayls, the same number in Pa·s/m.
Can it work out impedance from density and sound speed?
No. The characteristic impedance of a medium is its density times its sound speed, but this tool only changes the unit of an impedance you already have. Calculate the product first, then convert it here.
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/acoustic-impedance \
-H "Authorization: Bearer $KIT_KEY" \
-H "Content-Type: application/json" \
-d '{"value":1500000,"from":"MRayl","to":"rayl"}'const res = await fetch("https://api.kit.forhosting.com/conv/acoustic-impedance", {
method: "POST",
headers: {
"Authorization": `Bearer ${process.env.KIT_KEY}`,
"Content-Type": "application/json"
},
body: JSON.stringify({
"value": 1500000,
"from": "MRayl",
"to": "rayl"
})
});
const { task_id } = await res.json();import os, requests
res = requests.post(
"https://api.kit.forhosting.com/conv/acoustic-impedance",
headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
json={
"value": 1500000,
"from": "MRayl",
"to": "rayl"
},
)
task_id = res.json()["task_id"]<?php
$res = file_get_contents("https://api.kit.forhosting.com/conv/acoustic-impedance", false, stream_context_create([
"http" => [
"method" => "POST",
"header" => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
"content" => '{"value":1500000,"from":"MRayl","to":"rayl"}',
],
]));
$task = json_decode($res, true);body := bytes.NewBufferString(`{"value":1500000,"from":"MRayl","to":"rayl"}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/conv/acoustic-impedance", 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": 1500000,
"from": "MRayl",
"to": "rayl"
}Example response
{
"task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
"type": "conv.acoustic_impedance",
"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
The browser tool runs free on your device; the prepaid API charges $0.002 per successful item when ultrasound pipelines, sonar tools, or material catalogues need the same contract from servers and automation.
Supported units and how acoustic impedance conversion is computed
The converter accepts seven impedance families under stable canonical codes: Pa_s_m for pascal-seconds per metre, rayl for the MKS rayl, cgs_rayl for the centimetre-gram-second rayl, MRayl for the megarayl used in medical ultrasound and tissue tables, N_s_m3 for newton-seconds per cubic metre, kg_m2_s for kilograms per square metre per second, and dyn_s_cm3 for dyne-seconds per cubic centimetre. Friendly aliases such as pascal seconds per meter, mks rayl, si rayl, cgs rayls, mega rayl, megarayl, n s/m3, kg/m2/s, and dyne seconds per cubic centimeter are normalized case-insensitively so forms and APIs can pass either short codes or full names. Every request multiplies the input value by the exact Pa·s/m-per-unit factor for the source, then divides by the factor for the target.
Request shape, response fields, and unknown-unit errors
The error message names the bad field and lists the supported set so clients can correct forms without guessing. Negative values are allowed when you need signed impedance deltas in engineering pipelines; zero converts cleanly to zero in every target unit. Send a JSON body with three required fields: value as a finite number, from as the source unit string, and to as the target unit string. Aliases amount, quantity, Z, and impedance are accepted for value; unit_from and source for from; unit_to and target for to. On success the response echoes the canonical from and to codes, human-readable from_label and to_label strings, the converted result, the intermediate pa_s_m quantity in pascal-seconds per metre, the dimensionless factor from source to target, a short formula line suitable for UI display, the method tag acoustic_impedance_si_rayl, and the fixed list of units_supported. Missing value, non-finite numbers such as NaN or Infinity, missing unit fields, and any token that does not map to a supported unit fail with invalid_input and are not charged after the engine rejects the request. Identical inputs always yield identical JSON because the path is pure arithmetic with no randomness, no remote lookup, and no dependence on the wall clock, which makes the endpoint safe to pin in continuous-integration goldens and SDK contract tests. Extremely large magnitudes are rejected above a published safety cap so Worker isolates stay bounded while still covering every practical ultrasound, sonar, and architectural-acoustics inventory.
Browser use, API pricing, and everyday acoustic workflows
Switch to the prepaid API when a medical-imaging tool, sonar design app, material catalogue, NDT pipeline, or homework checker must convert acoustic impedance at scale under a stable KIT contract at $0.002 per successful item; validation failures that raise invalid_input do not consume balance after rejection. Pair this endpoint with sound-level or sound-intensity conversion when a product pipeline needs both impedance and pressure-related quantities, or call it alone when search traffic is specifically for rayls, cgs rayls, and pascal-seconds per metre rather than a general unit switchboard.
Integration use cases
Homework and NDT checkers
Acoustics courses and non-destructive testing tools call a prepaid deterministic endpoint to convert impedance units and get clear invalid_input on unknown tokens.
Technical questions
Which acoustic impedance units does this converter support?
Pa_s_m (pascal-seconds per metre), rayl (MKS), cgs_rayl, MRayl (megarayl), N_s_m3, kg_m2_s, and dyn_s_cm3. Full names and common aliases are accepted; unknown units raise invalid_input.
How do I convert 1.5 MRayl to rayls?
Send JSON with value: 1.5, from: "MRayl", to: "rayl". The response result is 1500000, plus a pa_s_m intermediate and a readable formula.