Saturnis
SPC that proves its math.Deploy today. Own forever.
Control charts, capability analysis, and Nelson rules — with Cassini. Serialization with Ephemeris. Self-hosted. Source-available. No per-seat fees.
Cassini
Statistical Process Control
Every calculation auditable. Every chart explainable.
Click any statistical value to see the formula, intermediate steps, and AIAG citation. No black boxes. No support tickets.
SPC Engine
Every chart type. Every rule.
X-bar & R, I-MR, CUSUM, EWMA, p, np, c, u. All 8 Nelson rules evaluated on every sample. Short-run SPC with Laney correction for low-volume production.
Transparency
Click any value. See the math.
Show Your Work mode underlines every statistical value. Click to see the formula, intermediate steps, and AIAG citation. Built for auditors.
Capability
Cp, Cpk, Pp, Ppk, Cpm.
Capability indices with full computation traceability. Box-Cox transformation for non-normal distributions. Subgroup and individual measurement modes.
Infrastructure
Your servers. Your database.
Docker deployment in minutes. SQLite, PostgreSQL, MySQL, or MSSQL — switch anytime. MQTT / Sparkplug B connectivity included. 300+ REST API endpoints.
Why manufacturers switch
Legacy SPC tools charge per-seat, lock your data in proprietary formats, and require vendor consultants to configure. Saturnis is the alternative.
No per-seat licensing
Deploy to your entire plant. One license covers unlimited users.
Your data, your database
SQLite, PostgreSQL, MySQL, or MSSQL. Switch anytime. Export everything.
Show Your Work
Click any statistical value to see the formula, intermediate steps, and AIAG citation. Built for auditors.
From shop floor to dashboard
MQTT / Sparkplug B connectivity included free. OPC-UA with Pro, RS-232 gage bridge with Enterprise.
Free forever. Pay when you need more.
Cassini ships as fully-functional open-source software under AGPL v3. Upgrade to Pro or Enterprise for proprietary rights, advanced integrations, and dedicated support.
Open
Free foreverAGPL v3
- ▷Full SPC engine with all chart types
- ▷All 8 Nelson rules + short-run SPC
- ▷Capability analysis (Cp, Cpk, Pp, Ppk)
- ▷CUSUM & EWMA analysis
- ▷MQTT / Sparkplug B (single broker)
- ▷ISA-95 equipment hierarchy
- ▷REST API (300+ endpoints)
- ▷Show Your Work transparency
- ▷Deploy on your infrastructure
- ▷Community support via GitHub
Pro
Most Popular$1,200 / plant / year
- ▷Everything in Open, plus:
- ▷Proprietary license (no AGPL)
- ▷Multi-plant management
- ▷PostgreSQL, MySQL, MSSQL
- ▷OPC-UA connectivity
- ▷Unlimited MQTT connections
- ▷MSA / Gage R&R studies
- ▷DOE (Design of Experiments)
- ▷Scheduled reporting & export
- ▷Standard support (email, 48hr)
Enterprise
$5,000 / plant / year
- ▷Everything in Pro, plus:
- ▷RS-232 / USB gage integration
- ▷Electronic signatures (21 CFR Part 11)
- ▷First Article Inspection (AS9102)
- ▷Multivariate SPC (T², MEWMA)
- ▷Anomaly detection (ML-based)
- ▷AI-powered chart analysis
- ▷SSO / OIDC authentication
- ▷ERP/MES connectors
- ▷Dedicated support with SLA
Built for regulated environments
Audit the Source
Every line of code is public. Review the SPC engine, Nelson rule implementations, and data handling yourself.
Your Infrastructure
Deploy on-premise or in your private cloud. Your quality data never leaves your network.
Standards-Based
ISA-95 equipment hierarchy, AIAG SPC methodology, AS9102 inspection reports.
Compliance-Ready
21 CFR Part 11 electronic signatures, complete audit trails, data retention policies.
No Vendor Lock-in
AGPL-licensed core. Switch databases, export data, fork the code. You're never trapped.
Enterprise Support
Pro and Enterprise licenses include SLA-backed support, priority fixes, and dedicated engineering.
Deploy in minutes. Own it forever.
One command to a production-ready SPC system on your infrastructure.
$ docker compose up -dNo credit card required. AGPL v3 licensed.