Open source · Self-hosted · AGPL-3.0

From calibrated instruments
to trusted results.

Open Gauge is an all-in-one registry for sensors, calibration coefficients, and certificates — with full version history, audit traceability, and ISO/IEC 17025-grade reproducibility.

opengauge.local / app / assets / OG-90421
Dashboard
Asset Registry
Locations
Procedures
Activity
v1.0.0 · self-hosted
JD

Reactor Inlet PT-01

Active
OG-90421
Reactor Bay · Main Plant  ·  Endress+Hauser · Cerabar PMP55
Export Sticker Edit
Health score
96/100
Last · Due
14 Feb 2026
14 Feb 2027
204days
Calibrations
3all-time
Overview Health Calibration Files Activity

General

Asset IDOG-90421
ManufacturerEndress+Hauser
ModelCerabar PMP55
OwnerProcess Eng. Team

Specifications

Physical quantityPressure
Range0 – 16 bar abs
Accuracy±0.05% FS
Output signal4–20 mA / HART

Built on open standards, not lock-in

ISO/IEC 17025:2017 JCGM 100:2008 (GUM) OpenAPI 3.1 PostgreSQL Docker Compose REST + JSON
Platform

Built for traceability, designed for engineers.

A modern stack for managing instruments at lab, plant, and fleet scale.

Version-controlled coefficients

Every offset, gain, and polynomial term is committed with diffs, authors, and rollback — just like Git.

ISO 17025 traceability

Immutable audit log, calibration history, and signed certificates built for accredited labs.

API-first, webhook-native

REST + OpenAPI 3.1. Every workflow in the UI is scriptable from CI, ERP, or edge gateways.

QR-tagged in the field

Print asset labels and scan them on a phone or tablet to jump straight to the record.

Sensor health & drift scoring

Calibration age, drift, and uptime fused into a single instrument health score.

Self-hosted by default

Docker Compose today, Kubernetes when you need it. Your metrology data never leaves your network.

Architecture

A clean, layered system you can audit.

No black boxes. No vendor lock-in. Open formats, open protocols, open source.

  • Stateless FastAPI workers — scale horizontally behind any load balancer
  • PostgreSQL as the single source of truth for every record
  • MinIO / S3-compatible storage for certificates and raw calibration files
  • Email reminders for upcoming calibrations and new certificate uploads
Web UI · QR Labels
REST API · Webhooks · OpenAPI 3.1
Calibration Engine · Versioning · Audit Log
PostgreSQL · MinIO (S3-compatible)
AGPL-3.0 · open source docker compose up -d
Product

Every instrument. Every change. Every certificate.

Asset registry

Searchable, taggable, exportable. Built for thousands of sensors, instruments, and reference standards.

OG-90421PT-01Valid
OG-90422TT-12Due soon
OG-90424FT-08Expired

Calibration history

Diff coefficients between revisions just like a code review.

offset = 0.008
+ offset = 0.012
  gain = 1.00041

Signed certificates

LaTeX-based PDF generation for cryptographically signed calibration certificates

CERT-2026-00821
SHA-256 verified
API

REST-first. JSON everywhere.

Scriptable from CI, edge gateways, lab notebooks, or your ERP. OpenAPI 3.1 schema published with every release.

GET /api/v1/assets/OG-90421
{
  "id": "OG-90421",
  "name": "Reactor Inlet PT-01",
  "type": "pressure",
  "status": "valid",
  "calibration": {
    "valid_until": "2027-02-14",
    "coefficients": {
      "offset": 0.012,
      "gain": 1.00041,
      "quadratic": 2.1e-6,
      "unit": "bar"
    }
  },
  "certificate_url": "/api/v1/certificates/CERT-2026-00821.pdf",
  "_links": {
    "history": "/api/v1/assets/OG-90421/calibrations"
  }
}
How it compares

Open Gauge vs. the usual alternatives

Compared by capability, not by brand — feature sets on specific named competitors change too often to compare fairly.

Capability Open Gauge Legacy on-premise Spreadsheets Generic cloud CMMS
Self-hosted, data stays on your infrastructure
Open source (AGPL-3.0), no license fees N/A
Immutable, Git-style calibration history Varies Varies
GUM (JCGM 100:2008) uncertainty budgets Varies Varies
Cryptographically signed certificates Varies
Documented REST API for every workflow Varies
Health scoring & drift prediction Varies
No per-seat pricing Varies
Works fully offline / air-gapped Varies
FAQ

Frequently asked questions

Is Open Gauge free to use?

Yes. Open Gauge is open-source software licensed under AGPL-3.0 — free to self-host, use, and modify. There's no license fee and no per-seat pricing.

Do I need to host it myself?

Open Gauge is designed to be self-hosted first — Docker Compose is the primary deployment target, and it runs comfortably on hardware as small as a Raspberry Pi or an Intel N100 mini PC. There's no hosted/SaaS version operated by the project at the moment.

Does Open Gauge work fully offline?

Yes, including certificate generation (the PDF engine is bundled in the Docker image) and authentication. This matters for air-gapped labs and secure facilities where internet access isn't available or allowed.

What does "Git-style calibration history" actually mean?

Calibration records, coefficients, and channel configurations are never overwritten — every change creates a new, immutable, timestamped record linked to the one before it. You can always see exactly what a sensor's calibration looked like at any point in time, and who changed what.

Does it calculate measurement uncertainty?

Yes — Open Gauge computes a full uncertainty budget following the GUM (JCGM 100:2008) methodology, and generates an ISO/IEC 17025-style statement of conformity comparing expanded uncertainty plus error against the tolerance.

Can I import data from my current spreadsheets or software?

Assets support ZIP-based import/export with a documented schema, so bulk-loading an existing asset registry is scriptable. See the API Reference for the exact import endpoint and payload shape.

What database and storage does it use?

PostgreSQL for structured data and MinIO (S3-compatible) for files like certificates and datasheets — both run as ordinary containers in the same Docker Compose stack, on infrastructure you control.

Can I try it before installing anything?

Yes — the live demo runs entirely in your browser against realistic sample data, no signup or backend required.

Your Instrumentation, Your Control

Start self-hosting your instrumentation stack today.

$ git clone https://github.com/open-gauge/open-gauge.git
$ cd open-gauge/infrastructure/docker && docker compose up -d
Contact

Talk to us

Questions, feedback, or need a hand self-hosting Open Gauge? Send a message, or email hello@opengauge.org directly.

Running Open Gauge in production? Reach out — we'd love to hear how your team is using it, and feature your company as one of the organizations trusting Open Gauge for their metrology tracking.