Human Protocol Is Bringing ‘CAPTCHA to Earn’ to Ethereum

Not as fun as “play to earn” but hey, it’s something.

AccessTimeIconAug 16, 2021 at 4:01 p.m. UTC
Updated May 9, 2023 at 3:22 a.m. UTC
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Human Protocol, the backbone for anti-bot system hCaptcha, has launched a CAPTCHA web app allowing users to get paid in HMT for solving image-annotation challenges. 

Many users will recognize hCaptcha on websites as that thing that forces you to identify fire hydrants in a picture grid. Google’s reCAPTCHA is the market leader though the decentralized upstart is gaining ground.

The service is used by websites including the Canadian government, video-on-demand streaming service Rakuten, research and advisory firm Gartner and the classifieds website Craigslist. 

The app gives users the chance to earn token rewards for proving their humanity while also refining the computer-vision algorithms that power artificial intelligence (AI) technologies, Human Protocol said in a press release. 

Ethereum mainnet launch

The Human Protocol Foundation also announced the launch of its protocol for “building decentralized marketplaces” on the Ethereum mainnet. Human was previously live on a private Ethereum network.

“Starting today, the protocol will be able to support the creation and completion of jobs on-chain while broadening the audience that’s able to contribute to AI and ML [machine learning] technologies,” said Harjyot Singh, Human Protocol’s director of technology.

In June, Human Protocol launched a tool that lets developers plug its “Proof-of-HUMANity” feature into cryptocurrency wallets. 

Last December, the project announced an expansion beyond Ethereum to the Polkadot parachain Moonbeam.


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