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postmarketOS scores 34/100 (Below expectations) on SINK's independent climate assessment, scored from public data only. Fees pay for the review, never the result. Last verified September 2026.
That places postmarketOS joint 505th of 847 companies scored, and joint 51st of 76 in SaaS / Digital Services.
Where postmarketOS sits among saas / digital services peers.
Among the 76 major saas / digital services brands we've scored, postmarketOS is tied =51st of 76, with 4 others.
Its three lowest-scoring questions, and what the evidence didn't show.
No formal emissions disclosure exists. postmarketOS is a distributed open-source project with approximately one paid full-time developer (Clayton Craft) supported by community funding, and all other contributors are volunteers working remotely on their own devices.
No Scope 3 data has been published.
No formal emissions trajectory data exists.
A score changes when the evidence does. We use new published evidence at the next rescore. Evidence that isn't public can count through an evidence review.
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Get in touch →Strongest on Controversies & Red Flags and Resource Use & Waste (8/10, 5/10). Weakest on Carbon Footprint — Operations and Carbon Footprint — Supply Chain (3/10, 3/10).
The 3 companies in the sector scoring nearest above postmarketOS.
Tuta operates on 100% renewable electricity since 2019 with minimal emissions and independent circular economy recognition.
See the breakdown →Reddit is a $2.2B public company with zero environmental commitments, no emissions reporting, and complete non-disclosure across sustainability metrics.
See the breakdown →The formula and all 15 sources.
Same ten questions for every company. No private weighting.
SINK = (0.3 × Base + 0.7 × Performance) × Scale15 sources used in this assessment. All publicly available. Each row shows which of the ten questions it informed.
“Clayton Craft works full time on the project supported by community funding. Every other developer is a volunteer.”
“fund ongoing infrastructure costs and expansions where appropriate, and purchase devices for development and testing”
“it becomes feasible to maintain devices even after OEMs have abandoned them”
“Overall, during financial year 2024 we added €8857 to our balance”
“they develop free and open source software to extend the life of consumer electronics”
“extending the usable lifespan of consumer electronics by providing users with full control over their hardware”
“Extending the life of your smartphone is one of the best ways to reduce its environmental impact as it reduces e-waste and lowers its carbon footprint”
“postmarketOS promote user autonomy, repairability, and long-term software support for consumer devices”
“Extending it by 24 months roughly halves the annualised environmental impact compared to a standard two-year upgrade cycle”
“How to organically grow and finance postmarketOS as a pioneer of Linux on Mobile”
“The SBTi's Target Dashboard lists companies and financial institutions that have set science-based targets”
“New research from InfluenceMap finds early evidence of entrenched fossil fuel interests”
“We have applied for a grant from NLnet's NGI Zero Core fund and it has been accepted”
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