Altcha

Brno, Czech Republic

Altcha is 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.

According to our data, Altcha is the 6th most popular captcha service on the web.
It has 0.1% of the captcha market share and is present on 0.02% of all websites.

πŸ’Έ Pricing

Altcha is available in both free and paid versions.

Free version βœ”οΈOpen source
ALTCHA Sentinel€24+/month

πŸ“Š Rankings and Market Share

πŸ† Altcha Awards

⚑ Sites Using Altcha

We have data on 566 websites that use the Altcha captcha service. Here is a list of some of the top ranked ones.

The highest rated site using Altcha is cuni.cz.

#WebsiteRankCountryLanguage
1 cuni.cz #5,726 Czech Republic Czech
2 cultura.gov.it #7,004 Italy Italian
3 fortiguard.com #8,664 United States English
4 19thnews.org #15,520 United States American English
5 mesopinions.com #23,074 France English
6 vsb.cz #28,030 Czech Republic Czech
7 rausgegangen.de #31,089 Germany English
8 efe.cl #32,181 Chile Spanish
9 softgarden.com #39,396 Germany German
10 tradetron.tech #41,874 English
11 mailinblack.com #50,846 France French
12 dbpedia.org #56,968 Germany British English
13 cfp.org.br #58,579 Brazil Brazilian Portuguese
14 forbrukerradet.no #59,437 Norway Norwegian BokmΓ₯l
15 asiapoisk.com #66,732 Russia Russian
16 metro.cl #78,686 Chile Spanish
17 bahnhof.se #86,966 Sweden Swedish
18 brainmarket.cz #87,501 Czech Republic Czech
19 jabkolevne.cz #94,949 Czech Republic Czech
20 emaerket.dk #105,172 Denmark Danish

πŸ“ˆ Usage Statistics

Most of the sites that use Altcha:

Most of the sites using Altcha are from Germany, France, and the United States.

  • Germany 20.3%
  • France 10.8%
  • United States 7.4%
  • United Kingdom 6.7%
  • Czech Republic 6.5%
  • Switzerland 5.7%
  • Austria 4.8%
  • Poland 3.4%
  • Sweden 3.2%
  • Other 31.2%

Most Altcha users speak English, German, or French.

  • English 33.8%
  • German 23.8%
  • French 10.5%
  • Czech 6.2%
  • Polish 3.5%
  • Spanish 3.3%
  • Swedish 2.4%
  • Dutch 2.2%
  • Italian 2%
  • Other 12.3%

The Altcha captcha service is especially popular on .com, .de, and .cz top-level domains.

  • .com 26.1%
  • .de 14.3%
  • .cz 5.7%
  • .org 4.6%
  • .ch 4.6%
  • .fr 3.5%
  • .at 3.2%
  • .se 2.3%
  • .co.uk 2.1%
  • Other 33.6%

The primary market segments for websites utilizing Altcha include business, marketing and merchandising, and online shopping.

  • Business 14%
  • Marketing/Merchandising 8.3%
  • Online Shopping 8.3%
  • Non-Profit/Advocacy/NGO 8.3%
  • Internet Services 7.6%
  • General News 7.6%
  • Education/Reference 6.4%
  • Real Estate 6.4%
  • Software/Hardware 5.1%
  • Other 28%

πŸ•΅οΈ Similar Technologies

These are some of the best Altcha 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$$$
4
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
10
MTCaptcha
Mountain View, California, United States

A GDPR and WCAG compliant enterprise captcha service.

Free tier$29+/month

πŸ†š Compare Alternatives

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πŸ’¬ Frequently Asked Questions

Where is Altcha's headquarters?

Altcha is located in Brno, Czech Republic.

Can I use Altcha for free?

Yes, there is a free version with limited functionality.

How much does it cost per month?

The pricing starts at €24 per month.

Which country uses Altcha the most?

The majority of Altcha users are from Germany.

Who uses Altcha?

According to our data, Altcha is used on hundreds of sites, including such established ones as cuni.cz, cultura.gov.it, and fortiguard.com.

Is Altcha used on government websites?

Yes, for example, it is used by cultura.gov.it.

How does Altcha compare to its competitors?

Altcha is a moderately popular captcha service, ranking ahead of 7 other captcha services we track.

What are the alternatives to Altcha?

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

Statistics were last calculated on .
For details, see our methodology and disclaimer.