Sinan Token Price Index · Governance rules

This document answers one question: why this index can be written into contracts, reports and policy. The answer, in short: the rules are set first. Every item below is a public commitment, and any change to them must also follow the process set out here.

1. What the index is

• Subject: the effective price per million output tokens of mainstream large models in China's model-API relay market. Effective price = panel list price × top-up rate ÷ exchange rate (USD/CNY at the day's central parity rate).
• Three numbers: discount ratio (market median effective price ÷ official reference price, snapshot), market median price (USD and CNY), index level (base 2026-09-02 = 100, chained by multiplying the geometric mean of day-over-day median price changes of models present on both adjacent days, unaffected by models entering or leaving).
• Three tiers: flagship (official price ≥ $20/M), mid-tier ($2–20/M), fast-tier (< $2/M); the whole-market figure is the median across models.
• Sample threshold: a model enters the index only when at least 15 sites carry a valid quote that day; a site's quote counts as changed only when two consecutive fetches agree; quotes marked "unverified" are excluded.

2. Release cadence and permanence

• daily: the previous day's data is updated before 05:00 Beijing time (pipeline starts at 03:00). If the day's pipeline fails, the page keeps the previous day with its date shown; no interpolation.
• Mondays: Sinan Rankings published, covering the previous Monday to Sunday.The 1th of each month: previous month's monthly report finalized.
• Permalink: /price-index.json (full series); /rank/<edition>; /report/<month>. Published editions and JSON files are never altered; corrections are appended as records while the original value is kept.

3. Change process

• Methodology changes(tier thresholds, sample thresholds, chained method, reference price sources): announced first on this page and in the monthly report,30 daysbefore taking effect; after that, the old and new definitions are published side by side 90 days, distinguished in the JSON by the `version` field.
• Field changes: add only; never remove, rename or change meaning.
• Reference price source changes(e.g. a vendor price change, or switching to a lower public-channel price): effective the same day, with source and effective time recorded in that day's snapshot; history is not retroactively altered.
• All changes are recorded in the `docs/METHOD.md` version history and the /corrections corrections log.

4. Exception handling

• Our-side failures: if market-wide uptime in a single probe round falls below 50%, it is treated as a network fault on our side and that round is excluded from every site's uptime; the one occurrence so far (2026-09-11 18:00 to day 12 2:00) has been excluded and disclosed.
• Data verification: four automatic checks (field drift, unit hints, price outliers, gap to the board leader); any hit is marked "unverified" and excluded from comparisons and boards, with a record kept when released.
• User error reports: anyone can report an error on any figure; once verified, it is recorded with attribution in the corrections log.

5. Conflicts of interest

• No paid listing, paid verification, paid ranking or advertising from any measured channel (relay site); outbound links carry no promo parameters and earn no commission.
• If paid data services are provided to model vendors or financial institutions in the future, the client category will be disclosed on this page; payment does not change any measurement definition, sample or ordering.
• Team members hold no equity or revenue share in any relay site.

6. Citation

• Chinese: 司南实验室，《司南 Token 价格指数》，date，https://compute.sinanlab.com/price-index
• English: Sinan Lab, "Sinan Token Price Index", date, https://compute.sinanlab.com/price-index
• Data files and field descriptions: /api-docs. Custom definitions, full history, method review: [email protected].

7. Version history

• v1 · 2026-09-16: first version of the governance rules. Index published daily from 2026-09-02.

Cite this page

Data may be freely cited and republished with attribution and a link. We take no money from measured channels, sell no rankings and add no referral parameters, so you can cite us as an independent third-party measurement.

Media, research institutions and financial institutions needing raw data or custom definitions: write to [email protected], see Press & researchers。