PSA density calculator
PSA density calculator: enter your values and see a clear result on this page. Free for individual checks; API from $0.002.
Run — free
Runs in your browser. Free, unlimited — your data never leaves this page.
How to use it
Enter your values in the form above. The tool checks them before calculating and shows the result on the same page.
Check your inputs
Use the labels and units shown next to each field. If something is missing or outside the allowed range, the page points to the field to fix.
Use it again or automate it
Use the browser tool for individual checks and the API when you need the same capability in an automated workflow.
What you can do with it
Get an answer now
Enter one set of values and see the result without building a spreadsheet or script.
Compare scenarios
Change one value at a time and rerun the calculation to understand what affects the result.
Automate repeated work
Use the API when the same calculation needs to run inside your product or workflow.
FAQ
What is PSA density?
PSA density (PSAD) is serum prostate-specific antigen divided by prostate volume from ultrasound, expressed in ng/mL/cm³. It places a PSA value in the context of gland size.
What formula do you use?
PSAD = PSA / prostate_volume, with PSA in ng/mL and prostate volume in cm³. The result unit is ng/mL/cm³. An educational comparison to the common 0.15 cutoff is included; it is not a diagnosis.
What happens if prostate volume is zero?
The request fails with invalid_input. Density is PSA divided by volume, so a zero volume is undefined and is rejected rather than returning Infinity or NaN.
Can PSA be zero? What if PSA is negative?
Zero PSA is allowed and yields density 0. A negative PSA is not a laboratory concentration and fails with invalid_input. Missing, non-numeric, NaN, and infinite values also fail.
What does the PSA density calculator cost?
The browser tool is free and runs locally. API requests use prepaid KIT balance at $0.002 per successful item; invalid input is not charged.
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/health/psa-density \
-H "Authorization: Bearer $KIT_KEY" \
-H "Content-Type: application/json" \
-d '{"items":["valor-1","valor-2"]}'const res = await fetch("https://api.kit.forhosting.com/health/psa-density", {
method: "POST",
headers: {
"Authorization": `Bearer ${process.env.KIT_KEY}`,
"Content-Type": "application/json"
},
body: JSON.stringify({
"items": [
"valor-1",
"valor-2"
]
})
});
const { task_id } = await res.json();import os, requests
res = requests.post(
"https://api.kit.forhosting.com/health/psa-density",
headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
json={
"items": [
"valor-1",
"valor-2"
]
},
)
task_id = res.json()["task_id"]<?php
$res = file_get_contents("https://api.kit.forhosting.com/health/psa-density", false, stream_context_create([
"http" => [
"method" => "POST",
"header" => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
"content" => '{"items":["valor-1","valor-2"]}',
],
]));
$task = json_decode($res, true);body := bytes.NewBufferString(`{"items":["valor-1","valor-2"]}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/health/psa-density", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)Example request
{
"items": [
"valor-1",
"valor-2"
]
}Example response
{
"task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
"type": "health.psa_density",
"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. |