Affärslivet Open-Source AI Index

Executive summary

The Affärslivet Open-Source AI Index ranks 18 economies on their contribution to open-weight AI — models whose trained parameters are publicly released. It combines three dimensions from Epoch AI: the number of open-weight models a country has released, the share of its models that are open, and its total model output, each normalised 0–100 and equal-weighted. United States leads. Openness is a deliberate strategy — China and Europe release far more of their models openly than the US — and open weights are the main counterweight to the concentration of AI compute. Every figure is sourced to Epoch AI, CC BY 4.0.

Key findings

The index — who builds open AI

The Affärslivet Open-Source AI Index ranks 18 economies on their contribution to open-weight AI — combining the number of open-weight models released, the share of a country's models that are open, and total model output into one 0–100 score. United States leads open AI development.

Most open-weight models released

By absolute count, these economies have released the most open-weight AI models — the raw material of the open ecosystem. Across all ranked countries, about 356 open-weight notable models have been released.

What the data reveals

Openness is a strategy, not an accident. China releases about 60.4% of its models with open weights against the United States' 39.6% — a deliberate bet on ecosystem and adoption over secrecy. Europe leans furthest open of all.

Two different countries win the two open races. On absolute open-model output, the largest model-builders dominate simply because they build more of everything. On open share — the percentage of a country's models released openly — smaller European and Asian economies lead, having made openness a national strategy.

Open weights are the counterweight to compute concentration: they let researchers and companies without frontier compute build on state-of-the-art models. The geopolitics of open vs closed AI is now as consequential as the compute race itself.

Highest open-weights share

Among countries with at least three notable models, these release the highest share of them with open weights — the clearest signal of an open-by-default strategy.

Full ranking — 18 economies

Every ranked economy with its composite score and normalised 0–100 score on each dimension.

Limitations & method

This is a transparent composite: each dimension is min-max normalised to 0–100 across the countries that report it, count/magnitude dimensions are log-scaled first, and the score is the equal-weighted mean of the dimensions a country reports (minimum 2 of 3). Scores are relative to the ranked set, not absolute.

It measures what is publicly tracked — undisclosed or sovereign activity is not captured, and equal weighting is a deliberate, disclosable choice. We publish the method and full data so others can reweight or extend it. Nothing is estimated by Affärslivet; every input traces to a named open dataset.

Scoreboard (machine-readable data)

Every headline indicator with its value, period, source and confidence. Free to reuse under CC BY 4.0.

↓ CSV · ↓ JSON

Methodology & verification

The Affärslivet Open-Source AI Index ranks 18 economies on their contribution to open-weight AI — models whose trained parameters are publicly released. It combines three dimensions from Epoch AI: the number of open-weight models a country has released, the share of its models that are open, and its total model output, each normalised 0–100 and equal-weighted. United States leads. Openness is a deliberate strategy — China and Europe release far more of their models openly than the US — and open weights are the main counterweight to the concentration of AI compute. Every figure is sourced to Epoch AI, CC BY 4.0.

Data dictionary

Frequently asked questions

Glossary

Open-weight model

A model whose trained parameters are publicly released, letting anyone run, study or fine-tune it. ↗

Open-weights share

The percentage of a country's notable AI models that are released with open weights — a measure of its open-AI strategy. ↗

Notable AI model

A model judged significant by Epoch AI on objective criteria — state-of-the-art performance, high citations or historical importance. ↗

Sources

• Epoch AI — Notable AI Models database (CC BY 4.0)

Related reports & data

• Countries Leading in AI
• National AI Power Index
• The Largest AI Companies