ALTCHA
by ALTCHA · Self-hosted, privacy-first captcha and bot protection
BenchRank score
Screenshots of ALTCHA
Homepage
Overview
ALTCHA is a captcha and bot-protection system with an MIT-licensed open-source core that works without cookies, tracking or external calls. The widget defaults to proof-of-work verification and escalates to a code challenge with audio for high-risk cases. ALTCHA Sentinel adds self-hosted threat intelligence, rate limiting and text classification; ALTCHA Cloud is the EU-hosted version.
- Best for
- Teams needing a self-hosted, GDPR- and WCAG-compliant captcha to replace reCAPTCHA on sites and forms.
- Pricing
- The open-source widget is free and ALTCHA Cloud costs €47, €137 or €187 per month excluding VAT with a 30-day trial, while self-hosted Sentinel prices are not shown.
- Runs on
- Self-hosted
Strengths and trade-offs
Strengths
- MIT-licensed core; no cookies, tracking or external calls
- 34 kB widget vs 85 kB+ Turnstile and 300 kB+ reCAPTCHA
- WCAG 2.2 AA with audio code challenge; 50+ languages incl. RTL
- Server libraries for 10 languages, plus Flutter and React Native
Trade-offs
- Cloud omits full Sentinel features like custom rules and data classification
- Cloud is capped at 1,000 API requests/day; 10,000 on Plus, 20,000 on Max
- Self-hosting Sentinel needs your own infrastructure and a supported SQL database
- No published price for self-hosted Sentinel beyond the 30-day trial
How ALTCHA markets itself
A structured read of the promise, proof and page design on ALTCHA’s captured homepage.
Homepage capture
“Captcha and Bot Protection”
- Angle: Security / trust-led
- Hero: Abstract graphic
Pricing
Published plans and prices from ALTCHA’s own pricing page.
How this score is made up
Each dimension is scored out of 100 and combined into the headline score using fixed weights.
MCP support
Whether an agent can drive the product through the Model Context Protocol, and how much setup that takes.
API quality
Public API surface: machine-readable spec, official SDKs, documented auth, errors, rate limits and versioning.
Documentation
Publicly reachable docs — coverage, freshness, code samples and machine readability.
Agent friendliness
How readable the site is to an automated client: llms.txt, structured data, server-rendered content, crawler access.
Pricing transparency
Whether real prices are published, self-serve signup exists, and usage costs are knowable without a sales call.
Changelog
A public, dated record of what shipped and when — the clearest signal that a product is still alive.
Marketing site structure
Whether the site answers a buyer's questions: clear positioning, the pages that matter, and accessibility.
Page speed
How fast the site loads for real visitors: Chrome UX Report 75th-percentile LCP, INP and CLS, with a Lighthouse mobile run standing in where a site has too little traffic for field data.
Operational trust
Status page and incident history, security disclosure, compliance and data-processing documentation.
Measured, but not part of the score
Useful to know, but not a mark for or against the product — so these do not affect the ranking.
Openness
Source availability, self-hosting, data export and open standards. Scored and shown, but not part of the composite — paid SaaS is not worse for being paid SaaS.
Maintenance
Release cadence and repository activity. Scored and shown, but not part of the composite — it is only measurable for open repositories.
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Where this comes from
The ALTCHA pages BenchRank reads when it scores the product — its documentation, release notes, status and security pages, and its repository where there is one.
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Is this your product?
Claim ALTCHA to manage its profile. Claiming lets you suggest edits to the descriptive fields — it never changes scores or rankings.