The D3 Efficiency Index

The standard unit of compute efficiency.

Every processor ranked A–F by how far it operates above the Landauer limit — the exact thermodynamic floor for erasing one bit. From quantum processors near the limit to legacy silicon five orders of magnitude above it.

Processors ranked

—

GPU · TPU · CPU · quantum

Most efficient

—

Median gap

—

above Landauer limit

Least efficient

—

Live ranking

The leaderboard

Sorted by efficiency — closest to the Landauer limit first. Filter by category, or click any row to locate it on the frontier chart below.

Rank	Processor	Category	Distance above limit	Gap	Power	Class

Efficiency frontier — power vs distance above Landauerlog–log

AB CD EF

Class distribution

Where would your fleet rank?

Run a free D3 audit on your own data center in 60 seconds and get your efficiency class — then see how you compare to the index.

Run free audit → Enterprise plans

Methodology. The D3 Efficiency Index expresses each processor's operating point as a multiple above the Landauer limit (k_B·T·ln2 per bit) at its operating temperature, mapped to classes A (<100×) through F (>50,000×). Figures are framework estimates derived from public thermal-design and throughput specifications, not vendor-measured benchmarks. Built on the D3 research series — DOI 10.5281/zenodo.20502577. Read the methodology →