carlos / platform Public

Carbon · build estimate

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332 entries across this repo's ledger branches could not be parsed and are not included below.

637 g CO2e

published range: 165 g – 10200 g — a single band spanning 62× (from 0.2591× to 16.03× the central figure — see Methodology below)

70786566 tokens counted — 243379 output, 69739836 cache read, 802959 cache write, 392 fresh input

capturing since 2026-09-28

100% of counted tokens (70786566 of 70786566) were priced using the single shared default row, not a model-specific figure — see the "Where these figures came from" table below.

381 g CO2e (42880512 tokens) of the total above is not attributed to any commit — work that produced no commit, not tokens that went missing. This is usage recorded before a branch's first commit-marker, or on a branch with no commits at all.

Accrued over time

2026-09-28: 79.9 g 2026-10-13: 114 g 2026-10-24: 443 g

Per session

SessionBranchModelOutputCache readCache writeInputCO2e
07894253-fbe8-42e3-8bd7-361304bbebdb census-approvals claude-opus-5-5 67557 18312921 347728 116 181 g
c4a04fdc-6a78-43c2-8a77-eb5fbb115271 litestream-oom-284 claude-opus-5-5 60923 12419157 111247 74 114 g
8a524042-c54d-483a-a5a0-e726dd55576f edge-replica-placements claude-opus-5-5 65571 7562910 105398 52 79.0 g
08eaa4e9-db04-408b-9066-d9b47fe013f8 edge-replica-placements claude-opus-5-5 14371 9162138 25842 42 72.7 g
622e3b2d-1bba-40c2-bd40-b65d02622c4c design-rootfs-apps claude-opus-5-5 17106 8299535 39971 50 68.2 g
d84c46de-fb02-477d-ba97-55426343f1df edge-replica-placements claude-opus-5-5 8543 7059207 20941 28 55.6 g
b3b1c17a-97a9-4af9-ac96-2b63ebeab957 census-approved-email-signin claude-opus-5-5 1400 3834737 3179 12 28.7 g
ca8a4ffe-d747-47ca-a557-58bea887a1c9 isolated-exec-layout claude-opus-5-5 6567 2955498 13939 14 24.4 g
734a1127-6834-4003-a701-7c72d35c51d6 self-serve-moves-4 claude-fable-5-1 1341 133733 134714 4 13.6 g

Factor table v1 · 2026-08-30

This figure is produced by factor table v1 (published 2026-08-30). It assumes a grid intensity of roughly 350 g CO2e/kWh and is never rendered at its source constant's full precision — that precision exists for traceability against the cited source, not because the grid intensity is known that exactly.

Where these figures came from

ModelRow usedCitation
claude-fable-5-1 default (fallback) Energy: Epoch AI, Josh You, "How much energy does ChatGPT use?", 2025-02-07 (https://epoch.ai/gradient-updates/how-much-energy-does-chatgpt-use) — 0.3 Wh for a typical GPT-4o query of 500 output tokens, and, in the appendix, 2.4 Wh for 10,000 input plus 500 output tokens. Take the appendix figure, not the 2.5 Wh the body quotes first and twice: the body states no output-token count, so only the appendix figure can be differenced against the 500-output-token baseline to isolate the input cost. Cache classes: no published energy study separates cached from fresh input, so these use Anthropic's published price multipliers as a proxy — cache read 0.1x and 5-minute cache write 1.25x base input price (Anthropic, "Pricing", https://platform.claude.com/docs/en/about-claude/pricing). Corroboration that the low end of the band is not absurd, though not the bound itself: Vartziotis et al., "From Tokens to Watt-hours", arXiv:2607.26571, Table 3 (https://arxiv.org/abs/2607.26571) gives 218.400 mJ per output token for Llama 3.3 70B = 60.7 Wh/Mtok, about a tenth of the figure above — but that model is accelerator-only, excluding cooling, host, networking, storage and PUE, so it bounds GPU silicon rather than the delivered CO2e this page publishes. Grid: US EPA, eGRID2023 Summary Data (https://www.epa.gov/egrid/summary-data).
claude-opus-5-5 default (fallback) Energy: Epoch AI, Josh You, "How much energy does ChatGPT use?", 2025-02-07 (https://epoch.ai/gradient-updates/how-much-energy-does-chatgpt-use) — 0.3 Wh for a typical GPT-4o query of 500 output tokens, and, in the appendix, 2.4 Wh for 10,000 input plus 500 output tokens. Take the appendix figure, not the 2.5 Wh the body quotes first and twice: the body states no output-token count, so only the appendix figure can be differenced against the 500-output-token baseline to isolate the input cost. Cache classes: no published energy study separates cached from fresh input, so these use Anthropic's published price multipliers as a proxy — cache read 0.1x and 5-minute cache write 1.25x base input price (Anthropic, "Pricing", https://platform.claude.com/docs/en/about-claude/pricing). Corroboration that the low end of the band is not absurd, though not the bound itself: Vartziotis et al., "From Tokens to Watt-hours", arXiv:2607.26571, Table 3 (https://arxiv.org/abs/2607.26571) gives 218.400 mJ per output token for Llama 3.3 70B = 60.7 Wh/Mtok, about a tenth of the figure above — but that model is accelerator-only, excluding cooling, host, networking, storage and PUE, so it bounds GPU silicon rather than the delivered CO2e this page publishes. Grid: US EPA, eGRID2023 Summary Data (https://www.epa.gov/egrid/summary-data).

Methodology

Grams are derived, not asserted, from two separately-arguable unknowns: watt-hours per million tokens per token class (energy), and grams CO2e per kWh for the grid inference is assumed to run on (grid) — grams = (Wh / 1000) × grid.

The published range (165 g – 10200 g) is one multiplicative band applied to the total, built from two sources answering the same question at each end: the energy term uses Epoch AI's own stated 0.1–4 Wh uncertainty around its 0.3 Wh baseline query; the grid term uses the EPA eGRID2023 subregions that actually host large cloud/inference capacity — RFCE (Northern Virginia / PJM East, the cleaner end) through MROW (Upper Midwest, the dirtier end) — rather than every eGRID subregion that exists.

The result spans a factor of 62×. That is narrower than the mixed-criteria alternative it replaces, which is not why it was chosen: it is the only span where both ends answer the same question, and the ruling would stand if consistency had widened it instead.

That envelope is an assumption about where inference runs, and it is the assumption a reader is most likely to want to reject. It has a real, named failure mode: inference actually running on a grid dirtier than MROW or cleaner than RFCE puts the true figure outside the published band entirely. The band is a stated assumption, not a guarantee.

Nor is the central figure itself conservative. The "floor" language elsewhere on this page is a claim about token coverage — tokens this page cannot see are missing, never double-counted — not a claim about these factors. The factors lean high in several places at once: the grid figure is the US national average against the roughly 272–288 g/kWh where inference actually runs (RFCE 271.8, NWPP 288.2 — the same eGRID2023 table cited above), all of a baseline query's energy is attributed to its output tokens, and cache writes are priced at 1.25× base input price — a proxy for renting five minutes of KV cache residency, not for the compute a cache write performs. A figure that is high on factors and low on coverage is not a bound in either direction.

What this number excludes

Every one of these undercounts except the bookmark-regression case above — so on token coverage, this figure is a floor far more often than a ceiling. That is a separate claim from the factor bias described in Methodology, and neither one cancels the other.