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NexCaptcha

Captcha type · Intuition Machines

hCaptcha solver API

Checkbox and invisible hCaptcha solved in one REST call. Returns the h-captcha-response token your form submit needs. Only solves are billed.

Also searched ash-captcha-responsehCaptcha checkboxhCaptcha invisiblehCaptcha sitekey solverhCaptcha image grid

Price
$2.18
per 1,000
Token acceptance
99.5%
Median solve
5.1s
p95 solve
11.6s

[ 01 ]What it looks like

A checkbox, then a 3x3 image grid asking you to pick every tile containing an airplane.

[ 02 ]Why it is hard

The label set rotates fast and mixes in adversarial and synthetic images chosen to break public classifiers, so a model trained on last month’s grids decays within weeks. hCaptcha also fingerprints the widget frame, so a token answered correctly inside a headless browser is often downgraded at verification. Invisible keys add a behavioural score on top, with no visible challenge to debug against.

[ 03 ]How we solve it

A dedicated hCaptcha worker pool answers the grids, and the classifier behind them is retrained on live traffic every week, so a new label set is covered in days rather than months. The widget frame is loaded in a full browser profile rather than a headless one, so the token is minted with a fingerprint that survives verification. Checkbox and invisible keys share one task type: set isInvisible and the rest is handled for you.

[ 02 ]Solve it in five lines

Solve it in five lines

Post the task, get the token. Our SDKs collapse creation, polling and retries into one call.

hcaptcha.sh
curl -s https://api.nexcaptcha.net/createTask \
  -H "Content-Type: application/json" \
  -d '{
    "clientKey": "YOUR_API_KEY",
    "task": {
      "type": "HCaptchaTaskProxyless",
      "websiteURL": "...",
      "websiteKey": "...",
      "isInvisible": "..."
    }
  }'

Required parameters

API task type
HCaptchaTaskProxyless
websiteURL
required
websiteKey
required
isInvisible
required
Difficulty
Moderate

[ 03 ]Where this one shows up

Where this one shows up

Web Scraping & Data Collection

Keep a crawl moving when challenges start firing at volume.

SERP & Rank Tracking

Daily rank runs that come back complete, not half collected.

QA & Test Automation

Run signup and checkout specs in CI instead of skipping them.

AI Agents & Browser Automation

One tool call returns a token and the agent keeps going.

Market Research & Data Aggregation

One call shape across sources that each protect differently.

Accessibility Automation

For people the audio challenge does not actually serve.

Security Research & Pentesting

Authorised testing, where a challenge hides the attack surface.

Owned-Account & Session Management

Re-login and session refresh, on accounts you already operate.

[ 05 ]Questions about this one

Questions about this one

The h-captcha-response token. Post it in the form field of the same name, and also as g-recaptcha-response on sites that mirror it there. Tokens are single use and expire in about two minutes.

Not for the standard checkbox or invisible widget. Send websiteURL and websiteKey and we solve proxyless. A proxy task is only worth it when the site pins the token to the session, or when the key is an Enterprise key carrying rqdata.

$2.18 per 1,000 solves, billed only when a token comes back. Median is 5.1s, p95 is 11.6s and success is 99.5%. Failed and timed-out tasks are not billed, so retrying costs nothing.

In the page source, on the div with class h-captcha as data-sitekey, or in the hcaptcha.com iframe URL as the sitekey query parameter. It is a UUID. Send it exactly as written, including case.

Solve your first thousand on us.

Create a key, paste it into the sample above, and watch a real token come back. No card, no sales call.

Get your API keyTalk to an engineer