Sentinel Pricing
ALTCHA Sentinel is a commercial product that requires a license for production use. We offer flexible plans tailored to startups, growing teams, and enterprise-grade deployments.
Purchase a License
To purchase a license, visit eu.altcha.org/license.
Enterprise licenses are also available via pro-forma invoice and bank transfer to an EU-based account. Contact us to arrange your purchase.
Free Trial
Get started with a 30-day free trial — no credit card required. The trial activates automatically after installation, giving you full access to all features so you can evaluate how ALTCHA Sentinel integrates into your environment before selecting a plan.
Includes all features from the Professional plan, unlimited verifications, and support for multiple domains.
Trial limitations: Single account and user only. Production use is prohibited — intended strictly for testing and evaluation purposes.
For trials or budget-conscious projects, the combination of Hetzner and Bunny.net provides a secure, production-ready setup with infrastructure costs starting at just €5 per month.
Licensing Plans
All licensing plans include the full set of features by default, unless a specific limitation is noted in the table below. This means core functionality, security, privacy, and accessibility features are always available across all plans.
Each plan complies with international data protection laws and supports accessibility standards for inclusive, lawful deployment worldwide.
Choose the plan that fits your organization’s size and operational needs:
| Starter | Professional | Enterprise | |
|---|---|---|---|
| Instances | 1 | 3 | Unlimited |
| Accounts | 1 | 10 | Unlimited |
| Users | 10 | 100 | Unlimited |
| Domains | Unlimited | Unlimited | Unlimited |
| Verifications | Unlimited | Unlimited | Unlimited |
| Throughput | Max. 1 RPS | Unlimited | Unlimited |
| External Redis | No | Yes | Yes |
| PostgreSQL | No | Yes | Yes |
| High Availability | No | Yes | Yes |
| Single Sign-On (SSO) | No | No | Yes |
| ClickHouse | No | No | Yes |
| OpenTelemetry | No | No | Yes |
| Software Updates | Yes | Yes | Yes |
| Price | €24 / month | €74 / month | €600 / month |
A 10% discount is available for biannual subscriptions, and 20% for annual subscriptions.
Refer to the Feature Definitions table for detailed explanations of each feature and plan limitation.
ALTCHA Sentinel is self-hosted (on-premise) software. Hosting services are not included in the licensing plans — additional costs may apply depending on your chosen provider.
Only the Professional and Enterprise plans support multi-instance deployments (clustering).
Lifetime Licensing
Professional and Enterprise plans are also available with a lifetime license — a one-time purchase with no expiration date. To purchase a lifetime license, contact support.
Plan Descriptions
Starter
Ideal for startups, small businesses, or personal projects with light usage and limited team access.
Choose this plan if:
- You’re a solo developer or part of a very small team
- Your application has low traffic or is in early development/testing
- You don’t need scalability features like clustering or high availability
- You’re testing ALTCHA Sentinel in a non-production environment
Professional
Recommended for production environments with moderate to high traffic.
Perfect for growing teams and mid-sized applications that require reliable performance and fault tolerance.
Choose this plan if:
- Your application handles moderate or high traffic
- You need external Redis and PostgreSQL for enhanced performance
- You require a fault-tolerant cluster (up to 3 instances)
- Your team needs access across multiple accounts
Enterprise
Designed for large-scale, mission-critical deployments requiring high availability, security, and enterprise-level integration.
Choose this plan if:
- You need a scalable, fault-tolerant cluster with many instances
- You require ClickHouse for advanced logging and analytics
- You need enterprise-grade support for continuous, reliable operation
- Your organization requires SSO and authentication protocol compliance (LDAP, OAuth 2.0, OpenID Connect)
Support Plans
Select a support plan based on your operational needs:
| Basic Support | Professional Support | Enterprise Support | |
|---|---|---|---|
| Response Time SLA | Best-effort | Within 24 hours | Within 4–8 hours |
| Avg. Resolution Time | Best-effort | Within a day | Within hours |
| Integration Review | No | Yes | Yes |
| Quarterly health checks | No | No | Yes |
| Security Patches | Yes | Yes | Yes |
| Bug Fixes | Yes | Yes | Yes |
| Communication Channels | Email only | Email only | Email and live chat (during CET business hours) |
| Price | Free | €24 / month | €300 or €600 * / month |
* The Enterprise Support plan starts at €300/month and includes email-only support. For live chat, choose the Enterprise Live Support plan at €600/month.
Feature Definitions
Here’s a breakdown of what each feature includes:
- Instances: Enables deployment across multiple instances with failover and redundancy. See Clustering documentation.
- Accounts: Maximum number of isolated logical accounts per plan, each with its own API keys, analytics, and data.
- Users: Number of users who can access the admin interface and manage configurations.
- Domains: Use ALTCHA Sentinel across unlimited websites or apps at no extra cost.
- Verifications: All plans support unlimited API requests and challenge verifications.
- Throughput: Starter plan limits requests to 1 per second. Other plans allow scaling based on your infrastructure.
- External Redis: Supports connection to a production-grade Redis-compatible database for performance and redundancy. See Performance Tuning.
- PostgreSQL: Enables PostgreSQL backend for performance and scalability. Required for clustering.
- ClickHouse: Used for analytics and logs, improving scalability and data availability. See Performance Tuning.
- OpenTelemetry: Allows collection of traces and logs with OpenTelemetry backends. See Monitoring.
- High Availability: Ensures operation continuity during node failure (requires multiple instances).
- Single Sign-On (SSO): Enterprise-grade authentication integration using protocols like OIDC or LDAP.
- Integration Review: Optional post-integration check to verify security and correct setup (by request).
- Quarterly health checks: Scheduled evaluations to ensure system performance, stability, and compliance.
If you’re unsure which plan is right for you, contact us for personalized guidance. Or, start with the free trial to experience ALTCHA Sentinel firsthand.