AI Price Index

When AI price-data quality actually matters. An open, dated, first-party-sourced record of AI model API prices over time.

Most price lists tell you what a model costs today. This one tells you what it cost on a given date, when that price was last confirmed, and links the first-party source that proves it. That provenance is the point: every value carries a verifiable source and a last_validated_at date, including historical ones.

Why this index

• Quality over coverage. We curate the models that matter and get them right, instead of chasing a long tail of variants and open-weight forks. Less noise, more signal.

• Verifiable, not scraped. Every price links to the provider's own pricing page, with the date it was confirmed and a confidence rating, and you can look up what any model cost on any past date.

• Automated freshness, human QA. Automation watches first-party sources for new models and price changes and cross-checks every number; a human signs off before anything is published.

• Data license: CC BY 4.0 (see DATA-LICENSE.md). Use it anywhere, just attribute.

• Tooling license: MIT (see LICENSE).

• Maintained by RoninForge. Source of truth, methodology, and corrections are all in the open.

Status: early. The schema, validation, and methodology are in place; coverage is being seeded flagship-first (see Roadmap). Prices can change and history is partly reconstructed; trust the confidence label and the source_url on each record, not this sentence.

Why it exists

No first-party provider publishes its own price history. Several open lists have broad current pricing, but none pairs each price with a dated, verifiable first-party source under a clear license, and none surfaces when a price was last validated. Tools that need to value past usage (what did this token cost back then) have nothing reliable to read. This fills that gap.

What is in here

schema/        JSON Schemas: the price record, the published per-model series, the index
examples/      illustrative-but-accurate records + series that the validator checks
data/          the published dataset (generated from the system of record; appears as coverage lands)
tools/         validate.mjs, a zero-dependency validator (run in CI and locally)
METHODOLOGY.md how prices are sourced, confirmed, dated, and corrected
CONTRIBUTING.md how to report or fix a price (a first-party dated source is required)

The price record

Every price is one record. The human-facing shape (what you contribute and what the validator checks) is defined in schema/price-record.schema.json. In short:

| field | meaning | | --- | --- | | provider, model_id, variation, unit | what is priced (e.g. anthropic / claude-opus-4-5-20251101 / input / usd_per_mtok) | | price_usd | the price for one unit | | effective_from, effective_to | the dates this price was in effect (effective_to: null = current) | | last_validated_at | when this price was last confirmed against its source | | source_url, source_kind, confidence | the first-party proof and how sure we are |

The published, served form is one file per model (schema/model-series.schema.json) plus a thin index.json (schema/index.schema.json); a client binary-searches a model's interval array by date.

Use the data

Three ways, depending on what you are building.

npm package (point-in-time lookups, no network)

npm install ai-price-index

The dataset ships bundled inside the package (no runtime network call), so a lookup is deterministic and reproducible against the version you installed.

import { current, priceOn, rate, meta } from 'ai-price-index';

current('claude-opus-4-8');        // today's input/output rate + the source that proves it
priceOn('gpt-4', '2024-01-01');    // the rate that was IN EFFECT on that date ($30 / $60 per Mtok)
rate('gpt-4', '2024-01-01');       // -> { provider, model, date, inputPerM: 30, outputPerM: 60 }
meta.dataModified;                 // the dataset date this install pins to

Short ids and a trailing [1m] display suffix resolve to the dated series (e.g. claude-opus-4-5 -> claude-opus-4-5-20251101); pass { provider } to disambiguate a bare model id. usdForRollup values a token rollup at a point in time with the shared cache multipliers (read 0.1x, write 1.25x / 2x). The package reproduces the same golden vectors as the other RoninForge pricing engines.

CLI (no install needed):

npx ai-price-index claude-opus-4-8                 # today's rate
npx ai-price-index gpt-4 --on 2024-01-01           # a past date
npx ai-price-index list --provider openai          # known models
npx ai-price-index claude-opus-4-8 --json          # machine-readable

JSON API (fetch the current snapshot)

The current prices are served as JSON with permissive CORS, so you can fetch them from a browser or a script. These are stable URLs (safe to depend on):

https://roninforge.org/data/ai-price-index/current.json   # current price of every model
https://roninforge.org/data/ai-price-index/index.json     # model list + per-model series file map

const { prices } = await (await fetch('https://roninforge.org/data/ai-price-index/current.json')).json();
const opus = prices.find((p) => p.model === 'claude-opus-4-8' && p.variation === 'input');
console.log(opus.price_usd, opus.src);  // 5  https://www.anthropic.com/news/claude-opus-4-8

For full price history (every dated interval, not just current), use the npm package or clone the repo. Per-model series filenames under models/ are content-hashed and not stable; do not hardcode them.

Clone the raw dataset

git clone https://github.com/RoninForge/ai-price-index
node tools/validate.mjs        # validate everything locally

When you publish anything derived from this data, attribute it: "AI Price Index by RoninForge, CC BY 4.0" with a link to this repository and the validation date of the values you used.

How to cite

Prices change and corrections supersede without deleting history, so cite a dated release to keep your snapshot reproducible. Machine-readable citation metadata is in CITATION.cff (GitHub renders a "Cite this repository" button from it).

Plain:

AI Price Index by RoninForge (https://roninforge.org/data/ai-price-index/), CC BY 4.0. Release <tag>, accessed <date>.

BibTeX:

@misc{roninforge_ai_price_index,
  author       = {{RoninForge}},
  title        = {{AI Price Index: dated, first-party AI model API prices over time}},
  howpublished = {\url{https://roninforge.org/data/ai-price-index/}},
  note         = {Release <tag>. Data licensed CC BY 4.0. Accessed <date>.}
}

For academic reuse, cite the DOI (Zenodo): 10.5281/zenodo.20730241. This is the concept DOI and always resolves to the latest version; each release also gets its own version DOI for an exact, reproducible snapshot.

Roadmap

Coverage is seeded flagship-first, deep on history: the leading models (Claude, GPT, Gemini) with their price history pushed back as far as it can be verifiably sourced, before widening to the long tail. Reconstructed history is labelled by confidence (archived / inferred / estimated) and never rendered with the same weight as a live-confirmed price.

Contributing

Found a wrong or missing price? Open an issue or a PR with the correct value and a first-party source URL plus the date you saw it. A contribution without a dated first-party source cannot be accepted; that rule is what makes this trustworthy. See CONTRIBUTING.md.