About
Atmospheris
International Standard
Serving atmospheric resources compliant with international standards.
Our Mission
Atmospheris provides the authoritative open-source implementation of the ISO 2533 Standard Atmosphere model — a reference framework used worldwide in aerospace engineering, atmospheric science, and industrial applications.
We make the International Standard Atmosphere accessible through interactive calculation tools, comprehensive libraries, and transparent, verifiable algorithms that anyone can inspect, use, and contribute to.
The Logo
The Atmospheris logo is a stylized cross-section of Earth's atmosphere — five curved bands, each representing one of the principal atmospheric layers, arranged from the densest to the thinnest.
The Name
Atmospheris blends two roots: the Ancient Greek atmos (ἀτμός, “vapour”) + sphaira (σφαῖρα, “sphere”), giving us atmosphere — the gaseous envelope surrounding Earth — and the suffix –is, a direct nod to IS in International Standard, the class of ISO documents that define globally harmonized technical references.
The name captures the project’s purpose in a single word: the atmosphere, made accessible through an International Standard.
Why It Was Built
Atmospheris was first developed as a companion tool for the revised ISO 2533 and ISO 5878 standards, giving standards users a dynamic calculator and clear reference materials to better understand the background and information described in the standards.
What We Build
Open-Source Libraries
Reference implementations in Ruby and TypeScript, providing the complete set of ISA calculations defined in ISO 2533.
Interactive Calculator
A professional web calculator with 3D atmosphere visualization, 2D charts, table generation, and unit-aware property display.
Standards Documentation
Comprehensive reference materials covering ISO 2533 constants, formulas, temperature layers, symbols, and related standards.
Standards Compliance
Published by
ISO/TC 20/SC 6
Standard Atmospheres
ISO Technical Committee 20, Subcommittee 6 — the body responsible for standardizing atmospheric reference models for aerospace, aviation, and meteorology worldwide.
SC 6 authored the foundational ISO/R 2533:1975 and the authoritative ISO 5878:1982, whose work underpins aircraft performance certification, spacecraft design, and weather forecasting.
Ribose provides technical support to ISO/TC 20/SC 6, developing and maintaining Atmospheris as the committee’s reference implementation of the International Standard Atmosphere.
Ribose is also the author of Metanorma, UniWord, Plurimath, and other open-source tools that bridge the gap between international standards and software.
Open Source
Atmospheris is released under the BSD-2-Clause license, allowing free use in both open-source and commercial projects.
Get Started
Try the interactive calculator, explore the standards, or integrate the library into your project.