{"id":21040564,"url":"https://github.com/pixelspark/webpow","last_synced_at":"2026-03-16T21:34:07.568Z","repository":{"id":31050030,"uuid":"34608716","full_name":"pixelspark/webpow","owner":"pixelspark","description":"Prevent form spam using in-browser proof-of-work (PoW)","archived":false,"fork":false,"pushed_at":"2015-04-26T11:27:14.000Z","size":128,"stargazers_count":11,"open_issues_count":2,"forks_count":2,"subscribers_count":4,"default_branch":"master","last_synced_at":"2025-01-23T11:45:49.196Z","etag":null,"topics":[],"latest_commit_sha":null,"homepage":null,"language":"HTML","has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":null,"status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/pixelspark.png","metadata":{"files":{"readme":"README.md","changelog":null,"contributing":null,"funding":null,"license":null,"code_of_conduct":null,"threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":null}},"created_at":"2015-04-26T11:24:12.000Z","updated_at":"2025-01-03T15:16:17.000Z","dependencies_parsed_at":"2022-08-07T16:15:17.417Z","dependency_job_id":null,"html_url":"https://github.com/pixelspark/webpow","commit_stats":null,"previous_names":[],"tags_count":0,"template":false,"template_full_name":null,"repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/pixelspark%2Fwebpow","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/pixelspark%2Fwebpow/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/pixelspark%2Fwebpow/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/pixelspark%2Fwebpow/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/pixelspark","download_url":"https://codeload.github.com/pixelspark/webpow/tar.gz/refs/heads/master","host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":243482944,"owners_count":20297909,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2022-07-04T15:15:14.044Z","host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":[],"created_at":"2024-11-19T13:47:10.350Z","updated_at":"2025-09-22T08:33:35.798Z","avatar_url":"https://github.com/pixelspark.png","language":"HTML","funding_links":[],"categories":[],"sub_categories":[],"readme":"# WebPoW\n\nPrevent form spam using in-browser proof-of-work (PoW)\n\n[Try WebPoW here](http://pixelspark.github.io/webpow/pow.html)\n\nWebPoW page is a proof of concept of using Web Workers to calculate a so-called 'proof of work'. A proof of work is a solution to a mathematical problem that can only be solved using trial-and-error; showing that you have found the solution is proof that you have performed a certain amount of computation (in reality, sometimes you 'get lucky' and find a solution fast, and sometimes it takes much longer; the average amount of work required however can be decided upon in advance).\n\nProofs of work can be used to prevent spam (e.g. on form submissions, e-mails, et cetera). Traditional CAPTCHAs prevent spam by exploiting the fact that computers cannot solve a particular problem easily, and that humans that can solve them are scarce/expensive/slow (but available in the regular use case). Proof of work, by contrast, exploits the fact that computational resources are scarce. While non-spamming users will typically have the resources to perform the computation once in reasonable time, spammers will have difficulty finding the resources to compute many proofs of work required to submit their spam. By requiring a 'proof of work' from the client before accepting any data, spammers are thus effectively blocked.\n\nUsing Web Workers, the proof of work computation can be performed in standard browsers in the background, while efficiently utilizing available computing power. This demo will attempt to spawn four worker threads (most browsers seem to be able to saturate four cores with this).\n\nUse cases include:\n* Prevention of automated form spam (require a PoW on submit)\n* Prevention of website crawling (require an increasingly difficult PoW on each new request)\n\n## Contact\n- Tommy van der Vorst\n- Twitter: [@tommyvdv](http://twitter.com/tommyvdv)\n- Web: [http://pixelspark.nl](http://pixelspark.nl)\n\n## License\n\nCopyright (c) 2014-2015 Tommy van der Vorst\n\nPermission is hereby granted, free of charge, to any person\nobtaining a copy of this software and associated documentation\nfiles (the \"Software\"), to deal in the Software without\nrestriction, including without limitation the rights to use,\ncopy, modify, merge, publish, distribute, sublicense, and/or sell\ncopies of the Software, and to permit persons to whom the\nSoftware is furnished to do so, subject to the following\nconditions:\n\nThe above copyright notice and this permission notice shall be\nincluded in all copies or substantial portions of the Software.\n\nTHE SOFTWARE IS PROVIDED \"AS IS\", WITHOUT WARRANTY OF ANY KIND,\nEXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES\nOF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND\nNONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT\nHOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,\nWHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING\nFROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR\nOTHER DEALINGS IN THE SOFTWARE.\n\nThis repository includes SHA-256 implementation in JavaScript (c) Chris Veness 2002-2014","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fpixelspark%2Fwebpow","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fpixelspark%2Fwebpow","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fpixelspark%2Fwebpow/lists"}