Cap

Lisbon, Portugal

Cap is an open-source, self-hosted reCAPTCHA alternative that verifies visitors without visual puzzles, tracking, or third-party services.

It uses a two-layer verification model that combines proof-of-work challenges accelerated with WebAssembly and Web Workers, including SHA-256 hashing and optional GPU-resistant time-locks.

It uses Redis/Valkey for storage and can be deployed with Docker.

According to our data, Cap ranks 12th among the captcha services we track.
It has 0.01% of the captcha market share and is detected on 0.002% of all websites.

It is especially popular in Chile, appearing on 0.1% of all websites in the country.

Statistics based on 4M+ analyzed websites. About this data

💸 Pricing

Cap is available for free.

Free ✔️ Open source

📊 Rankings and Market Share

⚡ Sites Using Cap

We have data on 70 websites that use the Cap captcha service. Here is a list of some of the top ranked ones.

The highest rated site using Cap is spectable.com.

#WebsiteRankCountryLanguage
1 spectable.com #125,032 American English
2 teletype.team #163,708 English
3 xcams-models.com #187,684 Luxembourg English
4 memorialmuseums.org #233,913 Germany German
5 trycap.dev #265,405 Portugal American English
6 artsencollectief.nl #372,967 Netherlands Dutch
7 aurusjoyeria.cl #385,774 Chile Spanish
8 heiminfo.ch #394,774 Switzerland German
9 joyasbaron.cl #397,624 Chile Spanish
10 fidentity.ch #457,237 Switzerland English
11 pharm-portal.ru #498,893 Russia English
12 laotradeportal.gov.la #534,627 Laos Lao
13 freedompress.org.uk #576,866 United Kingdom British English
14 ipax.at #605,795 Austria German
15 59.studio #636,781 American English
16 sfss.ca #660,402 Canada Canadian English
17 multihogar.cl #691,753 Chile Spanish
18 vgamers.cl #746,280 Chile Spanish
19 rutaoutdoor.cl #751,251 Chile Spanish
20 ortopediasuiza.cl #797,096 Chile Spanish

📈 Usage Statistics

Most of the sites that use Cap:

Most of the sites using Cap are from Chile, Switzerland, and Germany.

  • Chile 21%
  • Switzerland 12.9%
  • Germany 11.3%
  • Canada 8.1%
  • France 6.5%
  • United Kingdom 6.5%
  • United States 6.5%
  • Russia 4.8%
  • Spain 4.8%
  • Other 17.6%

Most Cap users speak English, Spanish, or German.

  • English 47.1%
  • Spanish 21.4%
  • German 14.3%
  • French 5.7%
  • Chinese 2.9%
  • Dutch 1.4%
  • Portuguese 1.4%
  • Arabic 1.4%
  • Basque 1.4%
  • Other 3%

The Cap captcha service is especially popular on .com, .cl, and .ch top-level domains.

  • .com 32.9%
  • .cl 17.1%
  • .ch 11.4%
  • .org 4.3%
  • .ca 4.3%
  • .de 4.3%
  • .fr 2.9%
  • .ru 2.9%
  • .co.uk 1.4%
  • Other 18.5%

The primary market segments for websites utilizing Cap include marketing and merchandising, online shopping, and education and reference.

  • Marketing/Merchandising 23.1%
  • Online Shopping 15.4%
  • Education/Reference 15.4%
  • Internet Services 7.7%
  • Business 7.7%
  • Health 7.7%
  • Blogs/Wiki 7.7%
  • Personal Pages 7.7%
  • Fashion/Beauty 7.7%

🕵️ Similar Technologies

These are some of the best Cap alternatives.

RankName
1
reCAPTCHA
Mountain View, California, United States

A Google service that protects websites from spam, fraud, and automated abuse by distinguishing human users from bots.

Free tier$8+/month
2
hCaptcha
San Francisco, California, United States

A security service for detecting and preventing human and automated abuse on websites and applications, often used as a drop-in alternative to reCAPTCHA.

Free$99+/month
3
Cloudflare Turnstile
San Francisco, California, United States

A user-friendly CAPTCHA alternative that verifies human visitors without requiring them to solve interactive puzzles or identify objects.

Free$$$
5
Friendly Captcha
Woerthsee, Germany

A European captcha service that protects websites from bots and automated abuse while prioritizing user privacy, security, and accessibility.

Free€9+/month
6
Altcha
Brno, Czech Republic

An open-source, privacy-first, self-hosted captcha alternative that uses a proof-of-work mechanism to protect websites, APIs, and online services from spam and unwanted content.

FreeOpen source€99+/month

🆚 Compare Alternatives

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💬 Frequently Asked Questions

Where is Cap from?

Cap is from Lisbon, Portugal.

Can I use Cap for free?

Yes, it is a free captcha service.
Moreover, it is an open-source solution and its code can be found on GitHub.

Which country uses Cap the most?

The majority of Cap users are from Chile.

Who uses Cap?

According to our data, Cap is used on at least 70 sites, including such established ones as spectable.com, teletype.team, and xcams-models.com.

Is Cap used on government websites?

Yes, for example, it is used by laotradeportal.gov.la.

What are the alternatives to Cap?

Alternatives and possible competitors to Cap may include reCAPTCHA, Altcha, and hCaptcha.

👉 See Also

🗃️ About This Data