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Meet Otto, your carbon advisor

No forms — just tell Otto about your flights, driving, or energy use in your own words and get a specific, explained recommendation in under a minute.

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Why

Why OpenCarbon is different

We run a curated marketplace, not an open listing service — every project is vetted before it goes up, not just accepted because a registry approved it.

Independently scored

Every project gets a Core Score, built on ICVCM's Core Carbon Principles — not our own marketing claims.

How we score projects

We link the bad news too

The 2023 Guardian/Die Zeit investigation into Verra credits is required reading. We link it ourselves, upfront.

Understand the risks

Run by a real person

Founder-run out of the Netherlands, with a name and a face behind it — not an anonymous shell company.

About OpenCarbon
How

From verified project to your certificate

A carbon credit isn't a promise — it's a tracked, one-time-use unit. Here's the mechanism behind every purchase.

Step 1

Verified against real standards

Projects are audited under an established methodology (e.g. Gold Standard, Verra, Puro.earth) before any credit is issued.

Step 2

Serial-numbered & registered

Each credit equals one tonne of CO2e and gets a unique serial number in a public registry — so it can't be sold twice.

Step 3

You buy from OpenCarbon

We source credits from registered projects and transfer them into your name the moment you check out.

Step 4

Retired — with your certificate

Your credit is permanently retired in the registry, and you get a certificate showing its serial number as proof.

Grounded in real standards, not marketing claims

Registry-tracked Third-party verified Serial-numbered, never resold Scored against ICVCM's Core Carbon Principles

Read the receipts before you buy anything, from us or anyone else

We'd rather you understand the risks in this market than trust us blindly. Start with our methodology and the questions people ask us most.

Trust & TransparencyFAQ

What we curate (not yet purchasable)

  • Agricultural Waste Biochar — Example Project

    Agricultural Waste Biochar — Example Project

    Sold out

    Agricultural Waste Biochar — Example Project

    88 Core ScoreCarbon removal
    €140,00 EUR
    €140,00 EUR
    Sold out
  • Clean Cookstoves — Example Project

    Clean Cookstoves — Example Project

    Sold out

    Clean Cookstoves — Example Project

    58 Core ScoreAvoidance
    €9,00 EUR
    €9,00 EUR
    Sold out
  • Coastal Mangrove Restoration — Example Project

    Coastal Mangrove Restoration — Example Project

    Sold out

    Coastal Mangrove Restoration — Example Project

    72 Core ScoreNature-based removal
    €18,00 EUR
    €18,00 EUR
    Sold out