Skip to content

Frontier model comparison

Research cut-off date: 2026-07-22. Status: Phase 4, not yet written. This file states the scope of the work, the arguments it owns, and the research required to complete it. It contains no findings, because none have been sourced. See the changelog for phase status.

Scope

Compares the closed-weight models positioned by their providers at the capability frontier, on specification and on results that were produced under compatible conditions. The comparison is constrained by the verification asymmetry: for these models, parameter counts, memory footprint, and energy per token are not observable, so the comparison is necessarily thinner than the open-weight one.

Comparison rules in force

  • Every row carries an evidence grade, a source, and a source date.
  • Results produced under different harnesses, sampling policies, or tool permissions are not placed in the same ranked column without a warning adjacent to the table.
  • Results whose conditions are unstated are never ranked against results whose conditions are known.
  • Provider-reported rows are labelled Grade C and are never used alone to rank one provider above another.

Research checklist

  • Define the inclusion rule for 'frontier' explicitly and defensibly, rather than adopting provider positioning.
  • Populate data/models.csv for every included model from its model card and API reference.
  • Record which specification fields are 'Not publicly disclosed' rather than omitting the row.
  • State in the file that Grade C rows are present and are not ranked against Grade A rows.
  • Regenerate the table with python scripts/generate_model_tables.py and commit the result.
  • Run python scripts/validate_tables.py --check-comparability.

Generated comparison

Generated from the data layer by scripts/generate_model_tables.py. Do not edit the region by hand.

Provider Model Release date Status Open weights Licence Architecture Total params (B) Active params (B) Modalities in Context window Max output Reasoning mode Tool use Deployment Evidence grade Source date
Anthropic Claude Fable 5 Not publicly disclosed generally_available no Proprietary Not publicly disclosed Not publicly disclosed Not publicly disclosed text|image 1000000 128000 optional function_calling first_party_api B 2026-07-22
Anthropic Claude Opus 4.8 Not publicly disclosed generally_available no Proprietary Not publicly disclosed Not publicly disclosed Not publicly disclosed text|image 1000000 128000 optional function_calling first_party_api B 2026-07-22
Anthropic Claude Sonnet 5 Not publicly disclosed generally_available no Proprietary Not publicly disclosed Not publicly disclosed Not publicly disclosed text|image 1000000 128000 optional function_calling first_party_api B 2026-07-22
Google Gemini 3.1 Flash-Lite Not publicly disclosed generally_available no Proprietary Not publicly disclosed Not publicly disclosed Not publicly disclosed text|image Not publicly disclosed Not publicly disclosed optional function_calling first_party_api B 2026-07-22
Google Gemini 3.1 Pro Not publicly disclosed generally_available no Proprietary Not publicly disclosed Not publicly disclosed Not publicly disclosed text|image 1000000 64000 optional function_calling first_party_api C 2026-07-22
Meta Meta Muse Spark 1.1 Not publicly disclosed preview no Proprietary Not publicly disclosed Not publicly disclosed Not publicly disclosed text|image 1000000 Not publicly disclosed Not publicly disclosed function_calling first_party_api B 2026-07-22
OpenAI GPT-5.6 Luna Not publicly disclosed generally_available no Proprietary Not publicly disclosed Not publicly disclosed Not publicly disclosed text|image 1050000 128000 optional function_calling first_party_api B 2026-07-22
OpenAI GPT-5.6 Sol Not publicly disclosed generally_available no Proprietary Not publicly disclosed Not publicly disclosed Not publicly disclosed text|image 1050000 128000 optional function_calling first_party_api B 2026-07-22
OpenAI GPT-5.6 Terra Not publicly disclosed generally_available no Proprietary Not publicly disclosed Not publicly disclosed Not publicly disclosed text|image 1050000 128000 optional function_calling first_party_api B 2026-07-22
xAI Grok 4.5 Not publicly disclosed generally_available no Proprietary Not publicly disclosed Not publicly disclosed Not publicly disclosed text 500000 Not publicly disclosed optional function_calling first_party_api B 2026-07-22