What is the AI Value Index?

Only models whose LMArena overall rating is at or above the median of models with both a rating and a list price are ranked. The score is 70 percent of where that rating sits between the floor and the leader, plus 30 percent of how cheap the blended price is on a log scale. Blended price is 25 percent input and 75 percent output. Index 100 is the median of models that pass the floor.

Why are some scores blank?

A score is shown only when a normalised name matches LMArena or Epoch. PowerfulBot does not impute missing benchmarks.

Methodology and sources

Name: PowerfulBot Index snapshot
Creator: PowerfulBot
License: https://powerfulbot-testing.powerfulbot.workers.dev/about/methodology

Value, without mixing units

Arena ratings, GPQA percents and Epoch’s Capabilities Index are different instruments. The Value Index uses only Arena overall rating and the list price. GPQA, LiveBench, SWE-bench and ECI are shown beside it and never averaged in.

The index no longer divides Arena points by the raw dollar price. That ratio handed first place to very cheap models. A model is ranked only from the top half of Arena ratings. Best overall weights quality at 70 percent and log-scaled price at 30 percent. Best value, on the same floor, divides Arena points by the natural log of blended price. Cheapest capable sorts that set by price. The full market table still lists models below the floor, with a blank score.

LMArena ratings and Epoch scores stay on the baked snapshot. Those files are a parquet set and a zip, which a free Worker cannot cheaply fetch and parse, so they change when the snapshot is rebuilt. List prices from models.dev and LiteLLM, the ModelPriceWatch series, Statuspage JSON, and headlines from RSS, arXiv, Hacker News and GitHub releases are fetched on a schedule and stored in Workers KV. A page reads that KV value first and falls back to the snapshot when a section has not been written yet. The cron is every 15 minutes and each tick refreshes one section: status on the open ticks, news on the hour, prices every six hours, then models and deals.

Price weather and history

History is the ModelPriceWatch series. The 30-day change compares the latest point with the point at least 30 days earlier. “Last move” is the most recent time the blended price actually changed. Price weather takes the median of those moves when they fall inside 120 days and landed on a later calendar day. Models that did not move are left out of the median. A steady lab had no settled change in the window. A tile that names one model is that model’s move, not a lab-wide median.

Orbs

On a wide screen the hero still carries four glass orbs. They link to models with the largest settled list-price moves. The tint is a lab colour, not a score. Phones omit them. The sculpture itself is a still, not a live simulation.

Speed

No latency number is published in this snapshot. scripts/probe-latency.mjs can measure a free tier when GEMINI_API_KEY is set, or an OpenRouter free model when POWERFULBOT_FREE_PROBE=1 and OPENROUTER_API_KEY is set. Results are our measurements. The catalog is never filled from OpenRouter.

Sources in this snapshot

models.dev — MIT. Retrieved 2026-10-23T02:38:47+00:00.
LiteLLM model_prices_and_context_window.json — MIT. Retrieved 2026-10-23T02:38:47+00:00.
ModelPriceWatch LLM Token Price History — CC-BY-4.0. Retrieved 2026-10-23T02:38:47+00:00.
LMArena leaderboard dataset — CC-BY-4.0. Retrieved 2026-10-23T02:38:47+00:00.
Epoch AI Capabilities & benchmarking — CC-BY-4.0. Retrieved 2026-10-23T02:38:47+00:00.

Not used

Artificial Analysis: Data Platform Terms restrict use in ranking or comparison products. PowerfulBot links to them and does not ingest scores.
OpenRouter: Terms restrict scraping and competing services. Not displayed. Optional internal cross-check is off unless POWERFULBOT_OPENROUTER_CROSSCHECK=1, and that file is not served.
Reddit API: Free tier is non-commercial. Not called. Discussions are not ingested.

Attribution for republished series: ModelPriceWatch (modelpricewatch.com), CC-BY-4.0. LMArena leaderboard dataset, CC-BY-4.0. Epoch AI, ‘Capabilities & benchmarking’, CC-BY-4.0, epoch.ai/benchmarks. models.dev and LiteLLM prices are MIT.