Built around recognised carbon standards

The carbon tools your spreadsheet can't replace

Project developers and consultants use The Carbon Workbench to run biochar yields, model project feasibility and check footprints - all built around transparent methodology references, all in one place.

No card needed·Not sure where to start? Use Project Intake.

Built around
Gold Standard Verra VCS BSI PAS 2060 ICROA
Biochar Analysis - 1,000 kg Live
Biochar yield
280
kg produced
Carbon locked
196
kg C stable
Gross CO₂e
0.719
tCO₂e gross
Net verified
0.611
tCO₂e net
Dry mass
850 kg
Biochar
280 kg
Carbon
196 kg
Net CO₂e
611 kg
GS Cookstoves AFR£11.80+0.40· GS Safe Water£13.20+0.20· Verra VCS REDD+£6.50−0.30· Puro Biochar EU£89.00+2.00· Verra VM0044£72.00-· GS Solar S.Asia£8.40−0.10· GS Cookstoves AFR£11.80+0.40· GS Safe Water£13.20+0.20· Verra VCS REDD+£6.50−0.30· Puro Biochar EU£89.00+2.00· Verra VM0044£72.00-· GS Solar S.Asia£8.40−0.10
15Professional tools
3Standards - GS, Verra, IPCC
£0To get started

The tool suite

Professional tools for
serious carbon work

Built for project developers, consultants and carbon teams. Free tools to get started - Pro unlocks feasibility modelling, project economics and PDF exports.

Free forever
Biochar calculator, carbon footprint analyser, CO₂e converter, water project calculator. No time limit, no card needed.
Pro - £49/mo
Feasibility, cookstove, solar, borehole and forestry tools, plus branded exports, share links and embeddable calculators.
New way to start
Not sure which tool you need first?
Use Project Intake to answer a few quick questions and get a recommended starting point based on your project type, stage and goal.
Open Project Intake →
Free

Biochar Carbon Calculator

Runs the full biomass → biochar → carbon → CO₂e chain. Tweak yield, moisture, permanence discount and process emissions and the numbers update instantly. Includes sanity-check ratios so you can spot if something's off before you share it.

Open Biochar Calculator →
1,000 kg woody biomass
Dry mass850 kg
Biochar produced238 kg
Carbon in biochar167 kg
Gross CO₂e0.611 t
Net verified0.494 tCO₂e
Free

Carbon Footprint Analyser

Scope 1, 2 and 3 for your organisation, built around BSI PAS 2060. Breaks down emissions by source and gives you a straight offset cost estimate at Gold Standard pricing. Useful for ESOS reports and CarbonZero assessments.

Open Footprint Analyser →
50 person organisation / yr
Gas heating8.2 t
Electricity16.6 t
Flights7.0 t
Commuting17.3 t
Offset cost @ £12/t £594/yr
Pro

Project Feasibility Modeller

Plug in household count, credit price and project life and you get annual credit volumes, total revenue and a simple ROI. Useful for sense-checking a project before you spend money on validation, or putting numbers together for a funder.

Open Feasibility Modeller →
5,000 household cookstove project
Annual credits12,000 tCO₂e
Annual revenue£144k
10-yr revenue£1.44M
Total costs£650k
Net profit£790k
Pro

Solar Energy Credit Calculator

Enter system capacity, peak sun hours and the local grid emission factor and get annual MWh generation, tCO₂e credits and lifetime revenue. Presets for West Africa, East Africa, South Asia, SE Asia and Latin America - the regions where most Gold Standard solar projects are developed.

Open Solar Calculator →
500 kWp solar project · West Africa
Annual generation657 MWh
Grid EF (W.Africa)0.82 t/MWh
Annual credits539 tCO₂e
Annual revenue @ £12/t£6,468
20-yr lifetime revenue£129k
Pro

Forestry & ARR Calculator

Estimate credits from afforestation, reforestation and revegetation projects under Verra VM0047 v1.1 - the new ICVCM-approved standard. Set hectares, forest type, permanence buffer and leakage deduction and see net annual credits with each deduction broken out line by line.

Open Forestry Calculator →
500 ha tropical dry forest · VM0047
Gross sequestration3,000 tCO₂e
Permanence buffer (15%)−450 tCO₂e
Leakage (10%)−255 tCO₂e
Net annual credits2,295 tCO₂e
30-yr revenue @ £15/t£1.03M
Pro

Verification Cost Estimator

The only tool of its kind. Choose project type and standard, enter your annual credit volume and price, and get an itemised breakdown of validation costs, annual verification fees, registry charges, net year-1 revenue and break-even timeline. Saves hours of VVB quote-gathering in early project planning.

Open Verification Costs →
10,000 tCO₂e/yr cookstove · Gold Standard
Gross annual revenue£120,000
Validation (one-off)£18,000
Annual verification£9,000
Net year 1£87,000
Break-even0.2 years

Try it now

Have a play - no sign-up needed

Adjust the live calculators below. Create an account when you want to save your numbers or access the full Pro suite.

Free · No sign-up · 2 minutes

Not a project developer?
Calculate your personal
Carbon Score

A data-driven personal footprint calculator covering 8 lifestyle categories - home energy, flights, car, food, shopping, digital, activity and more. Get a score, track your progress over time, and see exactly what would make the biggest difference.

Carbon Score andActivity Score - both 0-1000
24 achievements including Ground hugger, Planet plate, WHO Champion
"What if I went vegan / switched to EV / cycled to work?" scenarios
Track your score over time - see if you're improving
Get my Carbon Score →
Score preview
Carbon Score
340
/ 1000
Activity Score
680
/ 1000
Carbon Score vs UK average340 vs 520
0 best520 UK avg1000
Badges earned
Ground hugger
WHO champion
Green power
Climate champion
UK average is 520 · 2050 target is 125 · Your score updates in real time

No black boxes

You can see exactly where the numbers come from

Every emission factor has a source. Every formula is documented. Change any input and you see the effect immediately - which matters when someone asks you to justify a figure.

// Biochar carbon chain
dry_mass = input × (1 − moisture)
biochar = dry_mass × yield_pct
carbon_kg = biochar × carbon_pct
gross_co2e = carbon_kg × 3.667
net_co2e = gross × (1−process) × (1−perm)
// C→CO₂ molecular weight ratio
01
Verified emission factors
Factors pulled from IPCC AR6, UK DESNZ 2024 and Gold Standard-approved databases. We update them annually and note when we do.
02
Permanence discounting
Biochar stability is rated by H:C molar ratio. Permanence buffers follow Puro.earth and Gold Standard requirements - not made up.
03
Conservative defaults
We've set defaults at the cautious end of the range. You can change them, but they're there so your first result isn't embarrassingly optimistic.
04
Built by people who do this
Developed alongside carbon project developers with over 20 years of Gold Standard and CDM delivery behind them.

Learn and apply

Understand the market, the standards and the practical next step

The Learn section explains registries, verification, pricing, project design and embeds in plain English. It is there for developers, consultants and teams who want clearer context before they start modelling.

Start with a guide, understand the trade-offs, then move into the calculator, embed or intake flow that fits what you are trying to do.

Open the Learn hub →

Outputs people can trust

Show the working, then share the result

Transparent calculations
Formula-led estimates

Each calculator is designed to show the assumptions, emission factors and deductions behind the result so a developer can review the logic before using it in a proposal or feasibility note.

Try a calculator →
Pro outputs
Branded PDF and share links

Pro workflows turn calculator results into cleaner client-facing outputs: branded exports, saved assumptions and shareable links that are easier to send to a funder, colleague or client.

See Pro features →
Commercial workflow
From enquiry to portfolio

Pro keeps commercial work close to the tools: embedded lead capture, opportunity screening, portfolio records, stock views and cleaner proposal links for carbon teams.

Explore embeddable tools →

Embeddable Carbon Tools

Embed carbon tools on your website without building the tooling yourself.

The Carbon Workbench includes embeddable calculators, impact counters, project maps and lead-generation widgets for public websites, client portals and investor pages. Start with the embed docs, then use the supporting guides to see how these tools fit into real carbon-market use cases.

Pricing

Free to try. £49/mo for the full tool set.

Use the free tools to test the workflow. Upgrade to Pro when you want the full calculator library, saved assumptions, branded exports, share links and embeddable tools for your own site or client work.

Free
For trying TCW before you need client-ready outputs
£0forever
  • Biochar Carbon Calculator
  • Carbon Footprint Analyser
  • CO₂e Unit Converter
  • Safe Water Project Calculator
  • Methodology Selector
  • Personal Carbon Score
  • Good for first-pass estimates
Start free
Setup support
Optional help getting Pro live on your website, SharePoint or client workflow
Optionalone-off help when you need it
  • Not required to use Pro
  • Recommended tool and workflow setup
  • Embed install and QA support
  • Branding and default style setup
  • Stock Desk and basket workflow guidance
  • Proposal, share-link and PDF setup help
  • SharePoint or client website implementation checks
  • Short onboarding call for your team
Ask about setup →
Tool library All calculators unlocked

Project, business, finance and commercial tools in one account.

Outputs PDFs, CSVs and share links

Turn results into something you can send after a call.

Embeds Use tools on your own site

Configure calculators and widgets without building them yourself.

Branding Your logo, colours and styles

Keep exports and embeds closer to your own client workflow.

How we compare

Why not just use a spreadsheet?

For a one-off note, a spreadsheet is fine. The problem starts when you need repeatable assumptions, clean exports, share links, embeddable tools or client-facing outputs that do not break the moment someone edits the wrong cell.

Feature Carbon Workbench Spreadsheet Traditional GHG software
Carbon project calculator libraryBuild yourselfUsually corporate footprint focused
Saved assumptions and repeatable outputsEasy to overwrite
Branded PDF exports and CSV-ready outputsManual formattingOften limited or expensive
Shareable calculation linksSend a fileAccount access often needed
Embeddable calculators and widgets-Rare
Methodology and market contextSeparate notesVariable
Stock baskets and proposal linksManual-
Setup timeMinutesHours or daysWeeks
Starting price£0£0 + upkeepOften £500+/mo

FAQ

Sensible questions

Answered honestly.

How accurate are the calculations?

+

Calculations reference published sources such as IPCC AR6, UK DESNZ 2024 and methodology guidance from recognised carbon standards where relevant. The biochar workflow also reflects Puro.earth and Gold Standard permanence requirements. These are estimation tools - for formal credit issuance you'll still need independent verification.

Can I use these numbers in a Gold Standard submission?

+

The Carbon Workbench uses Gold Standard aligned methodology and is a strong starting point for project planning and feasibility. For formal submissions, you'll need a registered auditor to verify final numbers - but our tools will get you to the right ballpark quickly.

What's included in the free tier?

+

The free tier includes core calculators and guidance tools so you can test the workflow without a card. Upgrade to Pro for the full calculator suite, saved calculations, branded PDF and CSV-ready outputs, share links, embeddable tools, branding controls and the Stock Desk workflow.

Can I cancel Pro at any time?

+

Yes - cancel any time from your account. No long-term commitment. You keep Pro access until the end of your billing period.

Can teams use The Carbon Workbench together?

+

Yes - start with Pro for the full tool suite, branded exports, share links and embeddable calculators. Optional setup support is there if you want help configuring embeds, stock workflows, proposal links, SharePoint, client websites or team onboarding.

How do I know which methodology to use for my project?

+

Use the free Methodology Selector tool - pick your project type, scale, region and priority (credit quality vs volume vs speed) and it returns ranked recommendations with a plain-English explanation of why each standard suits your project. It covers cookstoves, water, biochar, solar, forestry/ARR, REDD+, agricultural land management, methane capture and blue carbon.

Can I share my calculations with colleagues or funders?

+

Yes - Pro users can generate a shareable link from any calculator. The link opens a clean read-only project card showing your key results and inputs, without requiring the recipient to have an account. Useful for sharing feasibility estimates with funders or project partners before a meeting.

How are emission factors kept up to date?

+

We update emission factors annually in line with UK DESNZ guidance and IPCC updates. Pro users are notified when factors change so you can rerun affected calculations.

Give it a go.
It's free.

No card, no commitment. If it's useful, great. If you need more, Pro is £49/mo.

Start free Talk to us

The Carbon Workbench - Explore the guides, then move into the right tool.

Start free Explore guides