We've made some big updates to carbon.txt thanks to funding from NGI Search.
Learn more in this blog post

Carbon.txt syntax

This page specifies the current v0.2 syntax for carbon.txt files.
Viewing syntax for

Carbon.txt v0.2

Latest versionLanguageValid fromValid to
trueTOML2025-01-23-

Syntax

PropertyParentTypeRequiredDescription
org[table]true
↳ disclosuresorg[[array]]falseLinks to documents that show your organisations sustainability data disclosures.
   ↳ doc_typedisclosuresstringtrueA slugified string representing the type of document you are linking to.
   ↳ urldisclosuresurltrueThe URL of the document you are linking to.
   ↳ domaindisclosuresstringfalseThe domain for which the disclosure applies.
[org]
disclosures = [
	{ doc_type = "webpage", url = "https://mycompany.com/sustainability", domain = "mycompany.com" },
	{ doc_type = "annual-report", url = "https://mycompany.com/carbon-emissions-2022.pdf", domain = "mycompany.com" }
]
PropertyParentTypeRequiredDescription
upstream[table]true
↳ servicesupstream[[array]]falseInformation linking your organisation to upstream providers you use.
   ↳ domainservicesstringfalseThe domain of the organisation providing the upstream service.
   ↳ service_typeservicesstringfalseA slug representing the service provided by the upstream provider.
[upstream]
services = [
    { domain = "cloud.google.com", service_type = "shared-hosting" },
    { domain = "aws.amazon.com", service_type = "cdn" }
]

Code sample

[org]
disclosures = [
	{ doc_type = "webpage", url = "https://mycompany.com/sustainability", domain = "mycompany.com" },
	{ doc_type = "annual-report", url = "https://mycompany.com/carbon-emissions-2022.pdf", domain = "mycompany.com" }
]
	
[upstream]	
services = [
	{ domain = "cloud.google.com", service_type = "shared-hosting" },
	{ domain = "aws.amazon.com", service_type = "cdn" }
]