Tuta Mail is an encrypted email and calendar service run by Tutao GmbH, a German software company based in Hanover with about 40 employees.
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Tuta operates on 100% renewable electricity since 2019 with minimal emissions and independent circular economy recognition. The critical weakness: no quantified targets, no GHG Protocol methodology, and unverified CO₂-neutral claims undermine credibility despite genuine resource-efficiency practices.
Tuta Mail (Tutao GmbH) scores 36/100 (Below expectations) on SINK's independent climate assessment, scored from public data only. Fees pay for the review, never the result. Last verified October 2026.
That places Tuta Mail (Tutao GmbH) joint 459th of 847 companies scored, and joint 47th of 76 in SaaS / Digital Services.
Where Tuta Mail (Tutao GmbH) sits among saas / digital services peers.
Among the 76 major saas / digital services brands we've scored, Tuta Mail (Tutao GmbH) is tied =47th of 76, with 1 other.
Its three lowest-scoring questions, and what the evidence didn't show.
No multi-year emissions data.
No GHG Protocol methodology, SBTi target, or quantified reduction pathway with timelines.
No GHG Protocol calculation published.
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 Energy Source (8/10, 7/10). Weakest on Emissions Trajectory and Targets & Commitments (2/10, 2/10).
The 3 companies in the sector scoring nearest above Tuta Mail (Tutao GmbH).
Snowflake has published no emissions data, no reduction targets, and no formal sustainability programme despite operating at scale ($3.6B revenue, ~7,000 employees).
See the breakdown →Entain has rebaselined climate targets, retired Scope 3 goals, and shown rising absolute emissions.
See the breakdown →The formula and all 9 sources.
Same ten questions for every company. No private weighting.
SINK = (0.3 × Base + 0.7 × Performance) × Scale9 sources used in this assessment. All publicly available. Each row shows which of the ten questions it informed.
“All Tuta servers are owned by us and hosted in highly secure German data centers”
“extends the lifetime of its servers through proactive maintenance and modular upgrades, significantly reducing electronic waste”
“Tuta runs its entire operation on 100% renewable energy”
“Target validation is carried out by SBTi Services, a wholly-owned subsidiary of the Science Based Targets initiative.”
“Tuta Mail has won the 'Deutscher Fairnesspreis' 2025 in the category 'Green Email and Hosting Provider'”
“This Friday we will join people around the world to demonstrate for a better future.”
“These allegations against Tuta, (formerly Tutanota), are false.”
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Tuta Mail is an encrypted email and calendar service run by Tutao GmbH, a German software company based in Hanover with about 40 employees. It markets privacy and sustainability as core differentiators and runs its own servers on 100% renewable electricity.
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