Verified credits from supported registries, listed at transparent prices. Retire on the spot, or hold credits in your account to retire or resell later.
Carbonmark is a carbon credit trading platform. Project developers list verified credits from supported registries. Buyers purchase any amount from 0.001 tonnes at a transparent price, then retire the credits on the spot or hold them in a Carbonmark account to retire or resell later. Our platform utilizes USDC to enable instant transaction settlement for our merchants and buyers.
Choose a project, enter the tonnes and the beneficiary, and pay by card, bank transfer or USDC. The credits are retired instantly after payment completion and you receive a public retirement certificate with a permanent ID. No account funding is needed.
Fund a verified Carbonmark account with USDC and buy credits at the listed price. They stay in your account until you retire them, or list them for sale at a price you set. Buy-to-hold settles in USDC only.
Open a Carbonmark account and verify it.
Fund it with USDC. Use Bridge, a Stripe company, to convert from your bank or card, or deposit USDC from any wallet or on-ramp you already use.
Browse the marketplace. Filter by registry, project type, country, vintage and price, and compare listings for the same project side by side.
Buy. Any amount from 0.001 tonnes, at the price shown, settled in USDC.
Retire or relist. Retire the credits against a named beneficiary and receive a certificate, or list them for sale at your price.
Showcasing what's currently available to buy on the marketplace, read from the Carbonmark API.
cheapest listing with supply, lowest to highest
The marketplace catalog holds 1,119 projects from 10 registries in total; the figures above count only those with supply for sale today.
Refreshed every six hours. Prices are per tonne of CO₂e at the cheapest listing with supply. Last read October 14, 2026.
Our carbon trading desk also facilitates trades across additional carbon standards and registry platforms, with liquidity available from hundreds of carbon projects beyond the listings above. If you are looking for inventory you do not see here, talk to our sales team.
Contact our sales teamEvery price on Carbonmark comes from a specific source you can see. Most credits are sold through listings on an order book: a seller names a price and a quantity, and the listing shows both.
Some credits are also available through advanced market makers, where a standardized class of credits trades at one price. The project page shows every source, its price and the supply left.
The figure shown as "from" is the cheapest listing that still has supply, so the rest of the tonnage may cost more. The minimum purchase is 0.001 tonnes, one kilogram of CO₂e.
Buy-to-hold purchases settle in USDC, a dollar stablecoin, so the price you see is the price you pay. Credits you buy sit in your Carbonmark account.
Retirements are recorded on a public blockchain, and every certificate carries an ID that resolves to that record, so a buyer, an auditor or a customer can check it without asking you.
How to retire carbon credits, and what the certificate proves
Companies and individuals offsetting their carbon footprint, from a single flight to an annual inventory. Buy carbon credits
Buyers who purchase credits ahead of a specific offsetting need, hold them in their account to retire or relist for sale later. Sell carbon credits
Projects listing credits from supported registries. Listing is free and sellers are paid in USDC. List your credits
Platforms and agents that quote, buy and retire through the Carbonmark API or our x402 endpoint. Explore the API
Listing is free for developers and for holders alike. Set a price, set a quantity, and the listing appears on the order book beside every other source for that project. Developers can list credits from supported registries, and holders can relist credits they bought.
Sell carbon creditsA seller lists verified credits at a price and quantity. A buyer purchases any amount from 0.001 tonnes and either retires the credits immediately or holds them to retire or resell later. On Carbonmark the price is shown before purchase and buy-to-hold trades settle in USDC.
Yes. Anyone can retire credits at checkout by card, bank transfer or USDC without funding an account. To buy and hold credits, an individual or a company opens a verified Carbonmark account and funds it with USDC.
Retirement at checkout works with a card or bank transfer. For buying and holding, you fund your Carbonmark account with USDC through Bridge, a Stripe company, from a bank account or card, or from a Web3 wallet if you already have one.
Yes. Credits bought with USDC are held in your Carbonmark account. You can retire them later against any beneficiary, or list them for sale at a price you set.
Each listing has its own price, set by the seller, and the project page shows every listing and pool with its price and remaining supply. Prices on Carbonmark currently range from under a dollar to several hundred dollars per tonne, depending on the project type, registry and vintage.
A marketplace lists individual credits from named projects with their own prices, so the buyer chooses exactly what they are buying. An exchange typically trades standardized contracts that bundle credits meeting a specification. Carbonmark is a marketplace: every purchase names the project, registry and vintage.