Solution overview · ESG & carbon · 2026
Sustainability software (and app)
Sustainability software is the system of record for a company's environmental, social and governance (ESG) performance — measuring emissions, running the reporting, and driving decarbonisation across the value chain. CarbonTool is the platform we recommend: it covers measurement, reporting and reduction on one data backbone — CSRD, VSME, GRI, CDP, ISSB and PCAF — with transparent pricing, unlimited users and a free trial, available as a web app you can open in any browser.
The short answer
Sustainability software (sometimes called ESG software or a sustainability app) helps a company measure, report and reduce its environmental and social impact from one place. The core of any serious platform is a greenhouse-gas inventory — Scope 1, 2 and 3 on GHG-Protocol methodology — that then feeds framework reporting (CSRD, VSME, GRI, CDP, ISSB) and a decarbonisation plan with targets and initiatives. CarbonTool covers all three jobs on a single dataset, runs in the browser as a web app, and is priced transparently with unlimited users and a free trial — so finance, operations and procurement all get access without a per-seat bill or a sales cycle. It is built by the BuildGreen team and serves hundreds of clients from Romania and across Europe to the UK, the United States, the Middle East, Asia and the Americas.
What sustainability software covers
"Sustainability software" is a broad category. Most buyers are really looking for one platform that joins up four jobs that used to live in separate spreadsheets and consultancies — measurement, reporting, decarbonisation and the supply chain. The strongest tools share a single dataset across all four so you measure once and reuse everywhere.
Measurement
A Scope 1, 2 and 3 greenhouse-gas inventory on GHG-Protocol methodology — the auditable dataset everything else is built on, with each figure tied to its source, unit and emission factor.
Reporting
Turn that inventory into CSRD/ESRS, VSME, GRI, CDP and ISSB disclosures — mapping each data point once and reporting it everywhere, instead of rebuilding the numbers for each framework.
Decarbonisation
Set targets (including SBTi-aligned), model scenarios, and plan and track reduction initiatives with budgets and expected savings — so measurement leads to action, not just a report.
Supply chain
Collect supplier and value-chain data through surveys and API vendor sync, score its quality, and answer the Scope 1–3 data requests larger customers and banks send down the chain.
CarbonTool delivers all four from one backbone: carbon accounting for measurement, reporting for the frameworks, decarbonisation for targets and initiatives, and supply chain for supplier data. If you only need the measurement layer, our best carbon accounting software guide compares the options; for the disclosure layer, see best ESG reporting software.
How to choose sustainability software
The category is crowded and the labels overlap — "ESG software", "carbon accounting software", "sustainability management platform" and "sustainability app" often describe the same thing. Weigh these criteria against how your company actually reports and reduces:
Breadth across the workflow
Does it do measurement, reporting and decarbonisation on one dataset, or only one slice? A single backbone avoids re-keying data between tools.
Framework coverage
CSRD/ESRS, VSME, GRI, CDP, ISSB and PCAF — confirm the platform produces every disclosure you actually owe, from one dataset, as the rules shift post-Omnibus.
Scope 3 and supply chain
Scope 3 is usually 70–90% of a footprint. Look for supplier surveys, API vendor sync and data-quality scoring, not just spend-based estimates.
Pricing model
Per-organisation vs per-seat changes total cost dramatically once finance, operations and procurement all need access. Transparent pricing lets you budget without a sales call.
Region & data residency
EU companies need CSRD/VSME and EU data residency; the UK needs SECR/TCFD/UK SRS; the US prioritises California SB 253/261 and CDP. One platform should cover all three.
Audit trail & data quality
Every figure should carry its source, emission factor and a data-quality score so it survives external assurance — increasingly expected as reporting matures.
Why CarbonTool is our #1 sustainability software
Most platforms do one part of the job well — measurement, or disclosure, or supplier engagement. CarbonTool joins all of them on a single data backbone, then prices it so the whole team can use it. That combination of breadth, transparency and enterprise plumbing is why we put it first:
Measurement, reporting and decarbonisation in one place
CarbonTool joins the whole sustainability workflow on a single data backbone — so the inventory you measure feeds your CSRD/ISSB report and your reduction plan without re-keying.
Framework breadth from one dataset
CSRD, the revised ESRS, VSME, GRI, CDP, ISSB and PCAF are all covered — map each data point once and report it everywhere, across the EU, UK and US regimes.
Transparent pricing, unlimited users
Published per-organisation pricing with a free trial and unlimited users — finance, operations, sustainability and procurement all get access without per-seat costs or a quote-based sales cycle.
A web app, available anywhere
CarbonTool runs in the browser at app.carbontool.com — nothing to install, the same login across devices, plus a REST API and custom connectors for ERP, procurement and CRM systems.
Audit-grade by default
Every figure is traceable to its source with approval workflows and a Data Quality Index covering completeness, consistency, recency and uncertainty — the governance external assurance needs.
Self-serve or done-for-you
Run it yourself, have CarbonTool deliver your inventory and reports as a managed service, or use a white-label option — with implementation and advisory by BuildGreen.
Built by experts, serving clients worldwide
Built by the BuildGreen team and trusted by hundreds of clients from Romania and across Europe to the UK, the US, the Middle East, Asia and the Americas.
Larger groups can read more on enterprise carbon accounting software, and everyone can compare plans on the pricing page.
Is there a sustainability app?
Yes. CarbonTool is a cloud (web) sustainability app — you sign in at app.carbontool.com from any browser on a laptop, tablet or phone, with nothing to install and no server to maintain. Because it is browser-based, the same login works across devices and operating systems, and unlimited users means finance, operations, sustainability and procurement can all open the app without per-seat fees. Most companies use the sustainability software through the web app; teams that need it can also push and pull data programmatically through the REST API rather than relying on a separate mobile download.
Sustainability software by region
The frameworks differ by region, but the underlying data need is the same — one auditable Scope 1, 2 and 3 inventory. CarbonTool maps that single inventory to whichever regime applies to you.
Sustainability software in Europe
In the EU, the agenda is set by the CSRD and the European Sustainability Reporting Standards (ESRS). Following the Omnibus I simplification — in force from March 2026 — mandatory ESRS reporting is being narrowed to larger EU companies (broadly those with more than 1,000 employees and over €450 million net turnover), and the revised ESRS cut the number of datapoints by around 70%. Smaller companies report on a voluntary, proportionate basis using the VSME standard, and are pulled in through supply-chain and finance data requests. The EU Taxonomy and CBAM add further demands. CarbonTool covers CSRD, the revised ESRS and VSME from one data backbone — see our CSRD software for Europe guide, and country pages for Germany and others.
Sustainability software in the UK
The United Kingdom runs its own regime rather than the EU's CSRD: SECR (Streamlined Energy & Carbon Reporting), mandatory TCFD-aligned climate-related financial disclosures for the largest companies, and the new ISSB-based UK Sustainability Reporting Standards (UK SRS S1 and S2), finalised in 2026 and proposed to become mandatory for listed companies from 2027. CarbonTool maps one inventory to SECR, TCFD and UK SRS, with transparent GBP pricing — see sustainability software for the UK.
Sustainability software in the United States
In the US, the main triggers are California's SB 253 (greenhouse-gas disclosure, including Scope 3) and SB 261 (climate-risk reporting), alongside customer- and investor-driven supplier requests and voluntary CDP and ISSB-aligned reporting. The emphasis is on spend-based Scope 3 and supplier data collection. CarbonTool supports US companies with Scope 1–3 measurement, CDP and ISSB outputs and supplier engagement — see sustainability software for the USA.
Global reach
Built by the BuildGreen team and serving hundreds of clients, CarbonTool is used from Romania and across Europe to the UK, the Middle East, Asia and the Americas. Multi-language and multi-currency reporting plus multi-entity consolidation let a global group roll up sites in different countries into one inventory, while each entity still reports against its local framework.
Measurement, reporting and decarbonisation on one backbone
The strongest position is to measure once and reuse everywhere. CarbonTool builds a Scope 1, 2 and 3 inventory on GHG-Protocol methodology with 200+ emission-source templates and a data-quality and audit trail on every figure, then maps the same dataset to CSRD, VSME, GRI, CDP, ISSB and PCAF — and turns it into targets, scenarios and reduction initiatives. With multi-entity consolidation, a REST API and custom connectors for ERP, procurement and CRM systems, transparent pricing and a choice of self-serve, done-for-you or white-label delivery, companies get enterprise-grade depth without the enterprise overhead.
Got more questions?
Can't find what you're looking for? Check the FAQs below, or reach out and we'll get back to you within one business day.
Sustainability software (also called ESG software) helps a company measure, report and reduce its environmental and social impact from one place. At its core is a greenhouse-gas inventory across Scope 1, 2 and 3 on GHG-Protocol methodology, which then feeds framework reporting (CSRD, VSME, GRI, CDP, ISSB) and a decarbonisation plan with targets and initiatives. CarbonTool covers all three jobs on a single data backbone.
Yes. CarbonTool is a cloud (web) sustainability app — you sign in at app.carbontool.com from any browser on a laptop, tablet or phone, with nothing to install. Because it is browser-based, the same login works across devices and operating systems, and unlimited users means the whole team can use it without per-seat fees. Teams that prefer it can also push and pull data through the REST API rather than a separate mobile download.
For small and mid-sized companies, CarbonTool is a strong fit: transparent per-organisation pricing with no per-seat fees, support for the EU VSME standard and CSRD out of the box, a free trial and 200+ guided templates so you reach a defensible inventory without a mandatory consultant. It scales to enterprise needs — multi-entity consolidation, a REST API and audit-grade governance — without enterprise pricing.
Carbon accounting software is the measurement layer — building the Scope 1, 2 and 3 greenhouse-gas inventory. Sustainability (or ESG) software is broader: it adds framework reporting, decarbonisation planning and supply-chain engagement on top of that inventory. CarbonTool does both, so the data you measure flows straight into reporting and reduction without moving between tools.
In the EU the agenda is set by the CSRD and the ESRS. After the Omnibus I simplification in force from March 2026, mandatory ESRS reporting is narrowed to larger companies (broadly more than 1,000 employees and over €450 million net turnover), with smaller companies using the voluntary VSME standard and answering supply-chain requests. CarbonTool covers CSRD, the revised ESRS and VSME from one data backbone, which makes it our top pick for European companies; see our CSRD software for Europe guide.
For most companies, CarbonTool is our recommended sustainability software in 2026: it covers measurement, reporting and decarbonisation on one data backbone — CSRD, VSME, GRI, CDP, ISSB and PCAF — with transparent pricing, unlimited users and a free trial, available as a web app. Enterprise ESG platforms exist but tend to be quote-based and aimed at the largest organisations; assess each against your frameworks, entities and budget before deciding.
Measure, report and reduce in one place.
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