ISO 14064-1 GHG Inventory Calculator | Six-Category Model & GHG Protocol Crosswalk
Consolidate your Scope 1, 2, and 3 totals into an ISO 14064-1:2018 conformant inventory — organised into the standard’s six emission categories, scored for report-readiness, and structured for third-party verification under ISO 14064-3.
What this calculator does. It is an auditor for your own inventory totals, not a footprint estimator. You bring greenhouse-gas figures already expressed in tonnes CO2e — built upstream on the GHG Protocol Corporate Standard or entered natively by ISO 14064-1 category — and the engine consolidates them, organises them into the standard’s six emission categories, and scores the inventory for report-readiness. It applies no emission factors and computes no footprint of its own.
Two entry modes. You can enter totals the way most organisations already hold them — by GHG Protocol scope — and the engine cross-walks them to the six ISO 14064-1 categories. Or you can enter natively by category. The crosswalk is labelled indicative throughout, because the GHG Protocol’s fifteen Scope 3 categories do not map one-to-one onto the standard’s six.
What ISO 14064-1 adds. The standard does not replace the GHG Protocol’s quantification rules or change any factor. It adds a conformance wrapper: explicit organisational and operational boundaries, a consolidation approach, an uncertainty assessment, a base-year and recalculation policy, and a documented inventory a third party can verify. This tool checks that wrapper is in place.
What is fixed by the standard, and what is a GreenCalculus default. ISO 14064-1:2018 specifies the structure and the principles, but it fixes no numeric materiality threshold, no completeness percentage, and no pass score. The significance threshold, recalculation trigger, reconciliation tolerance, and report-readiness gateway scores this engine applies are GreenCalculus engine defaults that operationalise the standard for scoring — they are not fixed by ISO 14064-1 and are not read from a data layer. They are stated plainly in the data-sources section so a reader can separate the standard’s requirements from this tool’s operationalisation of them.
Sec 5Boundary & period
Define the organisational boundary, the consolidation approach and the reporting period the inventory covers.
Sec 6GHG inventory
Enter your own emissions in tCO2e — already quantified (from GreenCalculus calculators, your GHG Protocol inventory, or upstream tools). Choose how you want to enter them; the engine maintains the ISO 14064-1 six-category model and cross-walks scope entry for you.
Scope entry is the common case (S1 / S2 / S3). Category entry lets you allocate across ISO 14064-1 Cat 1–6 natively.
Estimate within-boundary removals from area (optional)
Tier-1 annual sequestration from MasterBrain (IPCC AR6). For owned/controlled land inside your boundary — not for purchased credits.
Report by gas — 7 Kyoto baskets (optional)
ISO 14064-1 expects emissions reported separately by gas where significant. Enter CO2e per gas; the engine reconciles the sum against your gross total (±2%).
Sec 7Base year & recalculation
A base year and a recalculation policy let emissions be tracked consistently over time. The base year is recalculated after a significant structural change.
Sec 8Uncertainty & QA/QC
How uncertainty was addressed, and whether quality-assurance / quality-control procedures were applied to the inventory.
Sec 9Report metadata & exclusions
The mandatory GHG report contents: intended user, assurance intent, GWP basis, and any excluded categories with their justification.
Category exclusions register
For any indirect category you are not reporting, record why. ISO 14064-1 Sec 6/9 requires documented justification. Choosing “data unavailable” or “other” without a justification note caps the band at Not report-ready.
Audit mode adds the full per-datapoint conformance scoring table.
Enter your emissions by scope or category to build your inventory
A consolidated ISO 14064-1 inventory, a report-readiness scorecard, base-year comparison and an exportable Clause 9 report appear after you enter your first category.
This is a GreenCalculus alignment indicator against ISO 14064-1:2018, not an ISO certification and not a substitute for independent validation/verification (e.g. under ISO 14064-3). The readiness band reflects a transparent GreenCalculus interpretation of the standard’s published report structure; the scope↔category crosswalk is indicative, and the materiality, recalculation and gateway thresholds are documented defaults exposed in the methodology drawer and every export. This tool consolidates the emissions you supply — it does not estimate your footprint or look up emission factors. ISO 14064-1 is copyrighted; requirements are paraphrased and cited by clause. ISO 14064-1 standard notes.
Most organisations already have the numbers. What they do not have is an inventory — a set of totals with a declared boundary, a stated consolidation approach, an uncertainty assessment, and a structure an assurer can sign. The gap between a spreadsheet of tonnes and a verifiable inventory is exactly what ISO 14064-1 is for.
ISO 14064-1 does not change your numbers. It decides whether anyone can trust them.
ISO 14064-1:2018 organises an organisation's emissions into six categories — direct, imported energy, transportation, products used, products sold, other indirect — and requires a declared boundary, uncertainty assessment and verifiable documentation.
What this calculator determines
The calculator answers two questions that sit on either side of a recurring confusion: what is the consolidated inventory total, and is that inventory structured the way ISO 14064-1 requires. The first is arithmetic. The second is conformance.
The consolidated inventory total
The total is deterministic. The engine sums the figures you supply across the six categories — or across Scope 1, 2, and 3 if you enter by scope — and reports the inventory total in tonnes CO2e, with the per-category and per-scope subtotals that build it. No factor is applied and nothing is estimated; the figure is whatever your supplied totals add up to, and any reviewer working from the same inputs reconstructs it exactly.
The ISO 14064-1 conformance overlay
The overlay is interpretive. It scores the inventory against the things the standard asks for beyond a number: whether a consolidation approach is declared, whether the boundary is explicit, whether significant categories are addressed, whether an uncertainty assessment exists, and whether a base-year and recalculation policy are in place. It returns a report-readiness band rather than a pass mark, and a single hard gate can cap that band regardless of how complete the rest of the inventory looks.
ISO 14064-1 organises and verifies a GHG Protocol inventory — it does not replace its factors or recompute its numbers. The standard adds boundary discipline, uncertainty, and documentation. A correct total is necessary but not sufficient; an inventory you cannot verify is a number, not an inventory.
ISO 14064-1 vs the GHG Protocol Corporate Standard
The two are complementary, not competing, and most conformant inventories use both: the GHG Protocol to quantify, ISO 14064-1 to structure and verify. The table separates what overlaps from what ISO 14064-1 adds on top.
| Dimension | GHG Protocol Corporate Standard | ISO 14064-1:2018 |
|---|---|---|
| Primary role | Quantification — how to measure and categorise emissions | Conformance — how to structure, document, and verify an inventory |
| Emission structure | Scope 1, Scope 2, Scope 3 (15 categories) | Six categories (direct, imported energy, and four indirect) |
| Emission factors | References recognised factor sets; sets the accounting rules | Factor-agnostic — inherits whatever quantification basis you used |
| Boundary requirement | Consolidation approach (control or equity share) | Same approach, plus an explicit organisational and operational boundary statement |
| Uncertainty | Encouraged, less prescriptive | An uncertainty assessment is a documented requirement |
| Verification | Not the standard’s focus | Built for third-party verification under ISO 14064-3 |
What ISO 14064-1 adds in practice
Three things separate a conformant inventory from a footprint spreadsheet. The boundary is stated explicitly rather than assumed. Uncertainty is assessed and recorded rather than left implicit. And the whole inventory is documented in a form a verifier can trace from source data to reported total. The standard’s value is structural integrity, which is precisely what makes the resulting number defensible to a regulator, an assurer, or a board.
Organisational and operational boundaries
Before any emission is counted, two boundaries are drawn. Getting them wrong is the most consequential error in the whole exercise, because it changes which emissions belong to the entity at all.
Consolidation approach — control vs equity share
The organisational boundary determines which facilities and entities are inside the inventory. ISO 14064-1 recognises the same consolidation approaches as the GHG Protocol: financial control, operational control, or equity share. The choice is declared once and applied consistently, and it directly affects the total — a jointly owned facility is fully inside an operational-control inventory but only partially inside an equity-share one. The engine treats a declared consolidation approach as effectively required: the boundaries gateway is set high enough that an inventory with no stated approach cannot reach a report-ready band.
Operational boundary — categories, not just scopes
The operational boundary determines which emission sources are counted once the entities are fixed. This is where ISO 14064-1:2018 departs structurally from the older scope model: the 2018 revision reorganised emissions into six categories, moving away from the Scope 1/2/3 framing while remaining fully reconcilable with it. The categories are the canonical model this engine uses; scope entry is accepted and cross-walked to them.
The consolidation approach is declared, not inferred. Mixing approaches across facilities — operational control for one site, equity share for another — produces an inventory that does not reconcile and will not pass verification. Pick one approach, state it, and apply it to every entity in the boundary.
The six emission categories
ISO 14064-1:2018 distributes all emissions across six categories. The first two are direct and imported-energy emissions; the remaining four partition indirect emissions by source type rather than by the Scope 3 numbering practitioners may be used to.
Cat 1 · Direct
Direct emissions and removals from sources the organisation owns or controls — combustion, process, fugitive, and any direct removals, which are reported separately. Maps to Scope 1.
Cat 2 · Imported energy
Indirect emissions from imported electricity, heat, steam, and cooling. Reported on both location- and market-based bases. Maps to Scope 2.
Cat 3 · Transportation
Indirect emissions from upstream and downstream transport and distribution, business travel, and employee commuting.
Cat 4 · Products used by org
Indirect emissions from purchased goods and services, capital goods, fuel- and energy-related activities, and waste generated in operations.
Cat 5 · Use of products from org
Indirect emissions from the use and end-of-life of the organisation’s sold products, plus downstream leased assets and franchises.
Cat 6 · Other indirect
Indirect emissions from sources not captured by categories 3–5, including investments and any residual indirect sources.
Categories-to-scopes crosswalk
This is the table most practitioners arrive for. It maps the six ISO 14064-1 categories onto GHG Protocol scopes so an inventory built one way can be read the other. The mapping is indicative, not exact, because the Scope 3 categories distribute across several ISO categories rather than aligning one-to-one.
| ISO 14064-1 category | GHG Protocol equivalent |
|---|---|
| Cat 1 — Direct emissions and removals | Scope 1 (direct removals reported separately) |
| Cat 2 — Indirect from imported energy | Scope 2 (location- and market-based) |
| Cat 3 — Indirect from transportation | Scope 3 categories 4, 6, 7, 9 |
| Cat 4 — Indirect from products used by the organisation | Scope 3 categories 1, 2, 3, 5, 8 |
| Cat 5 — Indirect from use of products from the organisation | Scope 3 categories 10, 11, 12, 13, 14 |
| Cat 6 — Indirect from other sources | Scope 3 category 15 plus residual |
Enter your inventory the way you already hold it. If your data is organised by GHG Protocol scope — as it is for most organisations reporting under the Corporate Standard or the Scope 3 Standard — let the engine cross-walk it to the six categories. Re-keying everything into categories by hand is where mapping errors creep in.
How this calculator works
The engine runs two independent passes over the same inputs. The aggregation pass is pure arithmetic on tonnes; the conformance pass scores the inventory’s structure and applies the report-readiness gateways. The two passes share inputs but never share logic.
Inputs
Category or scope totals in tCO2e; the declared consolidation approach; optional within-boundary removals; an optional seven-gas split; uncertainty status; and base-year and recalculation-policy details.
Aggregation pass
Inventory total = sum of category totals (or scopes, cross-walked). Deterministic, auditable, and identical for any reviewer working from the same inputs. No factor applied.
Conformance pass
Scores boundaries, quantification, and inventory management against engine gateways and returns a report-readiness band. A hard gate can cap the band outright.
The report-readiness band is a structural check, not a verification. A high band means the inventory looks complete and internally consistent enough to take to an assurer; it does not mean the underlying tonnes are correct. Garbage totals entered into a well-structured inventory still produce a well-structured wrong answer — the engine checks the wrapper, not the measurement underneath it.
Worked example
An organisation completes its measurement and brings the following pre-aggregated totals to the inventory. All figures are illustrative and fixed for this example.
| ISO 14064-1 category | Value (tCO2e) |
|---|---|
| Cat 1 — Direct | 8,000 |
| Cat 2 — Imported energy | 12,000 |
| Cat 3 — Transportation | 9,500 |
| Cat 4 — Products used by org | 15,000 |
| Cat 5 — Use of products from org | 4,500 |
| Cat 6 — Other indirect | 1,000 |
| Inventory total | 50,000 |
Two things to read carefully. First, the total is just the sum — 50,000 tCO2e — and no factor or weighting touched it; the engine consolidated totals the organisation already held. Second, the significance test runs against this total: at a 5% threshold, any category above 2,500 tCO2e is flagged significant — here that is categories 1, 2, 3, and 4. Category 5 (4,500) is also above the line; category 6 (1,000) falls below it. A category that is below the threshold can be addressed more lightly, but it cannot simply be omitted without a documented justification — that omission is exactly what the hard gate guards against.
The same total can earn different report-readiness bands. An inventory with this total, a declared operational-control boundary, an uncertainty assessment, and a base-year policy reaches a report-ready band. An identical total with no stated boundary, or with a material indirect category dropped and no justification recorded, is capped below report-ready — the number is the same, the inventory is not.
Significance, base year, and uncertainty
Three inventory-management requirements decide whether the structure around the number holds up. ISO 14064-1 requires each of them in principle but fixes no figure for any; the values below are GreenCalculus engine defaults that operationalise them.
The significance threshold
The engine flags any category contributing more than 5% of the gross total as significant. This is a GreenCalculus indicative default, not an ISO 14064-1 figure — the standard requires that significant categories be identified and addressed but sets no percentage. The threshold drives a significance insight, not an exclusion licence: a category below 5% may be reported more lightly, but it is never silently dropped.
Base year and recalculation
A conformant inventory fixes a base year and a recalculation policy so that later totals are comparable. The engine applies a 5% change trigger as its recalculation-policy check — again a GreenCalculus default — flagging when a structural change (an acquisition, a divestment, a methodology revision) is large enough that the base year should be recalculated rather than the comparison quietly broken.
Uncertainty
ISO 14064-1 requires an uncertainty assessment, and the engine scores it categorically — not assessed, qualitative, or quantitative — rather than against a numeric error band. The categorical scoring reflects what the standard actually asks for: evidence that uncertainty has been considered and documented, with quantitative treatment stronger than qualitative, and either stronger than silence.
Uncertainty is not a licence to exclude. A category being uncertain is a reason to assess and document it, not to leave it out. Excluding a material indirect category because its data is rough — with no justification recorded — trips the hard gate and caps the inventory below report-ready, no matter how clean the categories you did include.
Verification readiness under ISO 14064-3
An ISO 14064-1 inventory exists to be verified. ISO 14064-3 is the companion standard that governs how a third party validates or verifies it, and the conformance pass is built around what that verifier will look for.
What an assurer checks
A verifier traces the inventory from declared boundary to reported total: that the consolidation approach is stated and consistently applied, that significant categories are present and quantified, that exclusions are justified, that uncertainty has been assessed, and that the base-year and recalculation policy are documented. The report-readiness band is this engine’s estimate of how much of that an assurer would find already in place — a rehearsal for the assessment, not a substitute for it.
An inventory you cannot verify is a number, not an inventory. ISO 14064-1’s discipline is what turns a defensible total into a verifiable one — and verification is the point at which the number becomes a claim anyone else can rely on.
Common boundary and categorisation errors
Mixing consolidation approaches
Operational control for one site, equity share for another. The inventory does not reconcile and fails verification. Declare one approach and apply it to every entity in the boundary.
Double-counting across categories
The same emission landing in both Cat 3 and Cat 4 because a source was mapped twice. Each source belongs to exactly one category; the crosswalk is a routing table, not a multiplier.
Dropping a material indirect category
Omitting a significant Cat 3–6 category because the data is hard to get, with no justification recorded. This trips the hard gate and caps the band below report-ready.
Treating uncertainty as exclusion
Leaving a category out because it is uncertain. Uncertainty is assessed and documented, not used as grounds for omission.
No declared boundary
Reporting a total with no stated organisational boundary or consolidation approach. The boundaries gateway is set so this alone keeps the inventory out of a report-ready band.
Forcing Scope 3 one-to-one
Assuming each of the fifteen Scope 3 categories maps to a single ISO category. They distribute across Cat 3–6; the crosswalk is explicitly indicative for this reason.
Scope and boundary of this tool
Knowing what the calculator does not do matters as much as knowing what it does. The boundaries below are deliberate for version 1.
| Aspect | In scope (v1) | Out of scope / roadmap |
|---|---|---|
| Quantification | Consolidates pre-aggregated tCO2e totals you supply | Does not apply emission factors or build the footprint |
| Entry mode | GHG Protocol scope entry (cross-walked) or native Cat 1–6 entry | Does not import directly from third-party inventory software |
| Conformance | Indicative report-readiness scoring against the structure | Not an ISO 14064-3 verification or certification |
| Removals | Optional within-boundary removal helper (area × land type) | Does not cover engineered removals such as DAC or BECCS |
A high report-readiness band is not verification. ISO 14064-1 conformance is established through independent assessment under ISO 14064-3; this tool indicates whether the inventory’s structure appears complete so you can prepare for that assessment. It does not replace it.
Data sources and methodology transparency
This calculator is intentionally light on external data, because it consolidates totals you supply rather than estimating a footprint. There is no ISO 14064-1 factor table to look up — the standard specifies a structure and a set of principles, not numbers.
What is read from the data layer
The engine applies no emission factors and does not estimate your footprint. Two optional, conditional reads touch the data layer and neither builds the headline total: an optional within-boundary removal helper that converts an area and a land type into an annual removal tonnage from IPCC AR6 Tier-1 forestry and soil factors, and an optional seven-gas split that passes IPCC AR6 GWP-100 values through as citation references rather than reading them to compute anything. Both are footnotes to the inventory, used only if you choose them. The value provenance of the inventory itself is your own upstream measurement, not GreenCalculus factors.
What is a GreenCalculus engine default
The 5% significance threshold, the 5% base-year recalculation trigger, the 2% per-gas reconciliation tolerance, and the report-readiness gateway scores are all GreenCalculus defaults that operationalise ISO 14064-1 for scoring. They are not fixed by the standard and are not read from a data layer. ISO 14064-1:2018 itself sets no numeric materiality percentage, no completeness percentage, and no pass score; the engine therefore frames every threshold as an indicative default and exposes each one in the methodology drawer and every export.
Footprint and GWP basis
The input inventory is typically built on the GHG Protocol Corporate Standard with IPCC AR6 GWP-100 characterisation, but the choice is yours and this tool inherits whatever basis you used — it performs no weighting of its own. For the full quantification logic underlying the inputs, see the ISO 14064-1 inventory methodology. The per-scope figures that roll up into this inventory can be built with the Scope 1 combustion calculator, the Scope 2 electricity calculator, and the Scope 3 spend-based calculator.
Where the inventory goes next
A completed ISO 14064-1 inventory is the input to almost every downstream claim. Set a science-based reduction pathway with the SBTi near-term target calculator, then demonstrate neutrality on the residual with the ISO 14068-1 carbon neutrality calculator or interpret a legacy declaration with the PAS 2060 carbon neutral calculator. Build the inventory first; every framework downstream consumes it.
Frequently asked questions
ISO 14064-1:2018 is the international standard for quantifying and reporting an organisation’s greenhouse-gas inventory. It organises emissions into six categories, requires a declared organisational and operational boundary, a consolidation approach, an uncertainty assessment, and documentation a third party can verify. It is factor-agnostic — it structures and verifies an inventory rather than computing one.
The GHG Protocol Corporate Standard quantifies emissions and organises them into Scope 1, 2, and 3. ISO 14064-1 structures and verifies the resulting inventory: it uses six categories instead of scopes, requires an explicit boundary and uncertainty assessment, and is built for third-party verification under ISO 14064-3. Most conformant inventories use both — the Protocol to measure, ISO 14064-1 to document and verify.
Category 1 is direct emissions and removals; Category 2 is indirect emissions from imported energy; Categories 3 to 6 partition indirect emissions by source — transportation, products used by the organisation, use of products sold, and other indirect sources. Categories 1 and 2 correspond to Scope 1 and Scope 2; categories 3 to 6 distribute the fifteen Scope 3 categories among them.
No. ISO 14064-1:2018 requires that significant categories be identified and addressed and that exclusions be justified, but it fixes no numeric materiality percentage and no completeness figure. This calculator applies a 5% significance threshold as a GreenCalculus engine default to operationalise the requirement — it is an indicative default, not an ISO figure.
Yes. The engine accepts GHG Protocol scope entry and cross-walks it to the six ISO 14064-1 categories, or you can enter natively by category. The crosswalk is indicative because the fifteen Scope 3 categories distribute across categories 3 to 6 rather than mapping one-to-one. Entering data the way you already hold it reduces the categorisation errors that come from re-keying by hand.
No. A high report-readiness band means the inventory’s structure appears complete and internally consistent — a declared boundary, significant categories addressed, uncertainty assessed, base-year policy in place. Formal conformance is established through independent assessment under ISO 14064-3. The band is a rehearsal for that assessment, not a substitute for it.