InferIndex README
The full upstream README, mirrored here for reference. Install config, tool schemas, adoption signals, and an original overview live on the InferIndex listing page.
InferIndex
InferIndex finds the cheapest provider for a given LLM, across 70+ tracked pricing sources — direct provider APIs and aggregators/routers — with price history and promotion detection.
Live API: https://api.inferindex.dev
Service status: https://status.inferindex.dev (external uptime monitoring)
This repository holds the public documentation, examples and (eventually) a client SDK for that API. The backend itself — collection, parsers, data model — lives in a separate private repository.
Example response as of 2026-09-18 — prices, providers and statuses change.
Prices are in USD per million tokens, converted at the day's ECB rate when the source publishes another
currency. blended_per_1M is (3 × input + output) / 4, a rough proxy for a typical chat workload.
Each offer appears once, at its cheapest source: via is "direct" or the aggregator it comes from, and
also_via lists other sources selling the same offer. promo is false unless a promotion was detected, in
which case confidence and price_before_promo are filled in.
Status
Early / actively developed. The API is public and free to use, without authentication, but there is no uptime guarantee, no versioned API contract yet, and endpoints or response shapes may change. If you build something on it, expect to adjust when they do. Feedback and issues are welcome.
Service status: https://status.inferindex.dev (external uptime monitoring). It shows current and past availability; it is not an uptime guarantee.
Why
Provider pricing pages disagree, change without notice, and rarely show what resellers actually charge for the same model. InferIndex collects prices directly from 70+ sources on their own schedule (from hourly to daily depending on the source), stores every change, and answers "who is cheapest for model X right now" from that history — client requests never trigger a live call to a provider.
Data freshness and limits
- Cache: successful responses carry
Cache-Control: public, max-age=300(5 minutes) (except/health/ready, never cached). On the custom domain, responses are additionally held in Cloudflare's edge cache for the same 5 minutes. - Collection frequency: most sources are polled hourly; a few (exchange rates, model catalog) once a day.
- Rate limits: 60 requests per minute per IP on
/cheapest,/historyand/resellers, counting only requests not answered from cache. An optional API key (x-api-keyheader) raises this to 300 requests per minute per key; free keys will be offered, self-service sign-up isn't available yet. An invalid key returns 401. Over the limit, requests get429. The MCP server has its own limits, see Use with AI assistants. - Cost estimate: add
prompt_tokens,output_tokens,cached_ratioandrequests_per_dayto/cheapestor/resellersto get an estimated cost per request and per month for each offer, andsort=estimated_costto rank by it. See docs/api.md. - Hidden tiers by default: degraded service tiers (
flex,batch— lower priority, variable latency, in exchange for a lower price) are excluded from/cheapestand/resellersunless you ask for them withinclude_tiers=flex,batch. The number hidden is reported inhidden_tiers.
Reliability of the prices — read this before trusting a number
Data corrections are listed in the changelog.
InferIndex is a comparison tool, not a source of truth. Treat every price as "what our collector last saw", not as a guarantee of what you will be billed:
- Prices come from public APIs and, for some sources, HTML pages parsed with source-specific code — a page redesign can silently break a parser until it's caught.
- A price that looks unusually low may be a promotion, a misparsed unit, or a provider that hasn't updated its page yet. InferIndex applies guard rails (rejecting implausible prices, quarantining sudden jumps, flagging outliers against a second reference source) and reports detected promotions with a confidence level, but these are heuristics, not certainties.
- Reseller aggregators can add their own margin. When a source's pricing model isn't fully understood, it is either excluded or flagged.
- Always confirm the price on the provider's own page or dashboard before committing to real spend.
Endpoints
| Route | What it does |
|---|---|
GET /cheapest?model=deepseek/deepseek-v3.2 | Cheapest offer across all active sources, and every matching offer deduplicated and sorted |
GET /resellers?model=deepseek/deepseek-v3.2 | Current prices across every reseller (direct and via aggregators), one line per source, paginated beyond 100 offers |
GET /history?model=deepseek/deepseek-v3.2&days=30&granularity=day | Price history, paginated by cursor |
GET /models?search=deepseek | Search tracked models |
GET /trending | Up to 10 models currently getting attention, recomputed about every 6 hours |
GET /index?series=market | Weekly market index, every Monday from 2026-10-05 — see the methodology |
GET /health/live | Liveness only: the service is up, no database access |
GET /health/ready | Readiness: data freshness and scheduler health, see below |
/mcp | MCP server for AI assistants, see Use with AI assistants |
/cheapest filters
sort=blended\|input\|output— sort order (defaultblended)min_context=100000— minimum context windowquantization=fp8,bf16— accepted quantizationsmin_uptime=95— minimum 30-minute uptime (%), as observed by an aggregator (not measured by InferIndex)tools=true,json=true,vision=true— only offers declared to support tool calling, JSON output, image inputregion=eu— only offers processed in that region (eu, us, cn, uk, ch, sg, id, my, vn, kr, jp, in, ca, au), per the providers' official documentsno_training=true— only offers whose providers state they don't train on promptsno_waitlist=true— only providers whose signup is open to everyonestrict=true— also drop offers for which the filtered data is unknown (by default they're kept and flagged inunverified, counted infilters_unknown)include_tiers=flex,batch— include degraded service tiers (excluded by default, see above)explain=true— list every excluded offer with its reason codes (anexplanationsummary is always included)
Offers also carry conditions (data region, retention, training on prompts, and what it takes to open an
account — each with its official source link), quantization_source (whether the compute precision is declared
by the source or inferred), and, on /resellers, reliability from the providers' official status pages. See
docs/api.md.
/history
granularity=raw returns one row per price change; day / week (weeks start Monday) return one point per
period and per offer (provider, quantization, variant) with min, max and last price. Use days or from/to
for a period, or at=2026-09-15 for the prices in force at a given moment. Prices are converted to USD at the
ECB rate of the day of the price.
Model search (/models):
Example response as of 2026-09-15 — prices, providers and statuses change.
/health/ready
Example response as of 2026-09-15 — prices, providers and statuses change.
status is ok, degraded (a non-critical part is having trouble — see the degraded array for which) or
unavailable (no usable price data). HTTP 200 for ok/degraded, 503 for unavailable. Useful as an
uptime-monitor target if you depend on this API.
Full route and parameter reference: docs/api.md.
Use with AI assistants (MCP)
InferIndex is also available as a remote MCP server, so an AI assistant can look up prices for you:
- Endpoint:
https://mcp.inferindex.dev/mcp(Streamable HTTP) (https://api.inferindex.dev/mcpalso works, as an alias) - Listed in the official MCP Registry as
io.github.InferIndex/inferindex. - Read-only, no authentication. An API key can be passed in the
x-api-keyheader. - Limits: 120 requests per minute per IP on
/mcp, at most 10 JSON-RPC messages per batch and 64 KB per request (otherwise400or413with JSON-RPC error-32600). Over the rate limit:429with JSON-RPC error-32000. Each tool call also counts toward the limit of the API route it uses (/cheapest,/resellers,/history).
| Tool | What it does |
|---|---|
search_models(query) | Find the exact id of a model |
cheapest(model, …) | Cheapest offers, with the same filters as /cheapest (min_context, tools, json, vision, region, no_training, no_waitlist, strict, include_tiers), optional usage (prompt_tokens, output_tokens, cached_ratio, requests_per_day) and limit |
compare_providers(model, sort, limit, …) | Every offer, one line per provider, with usage conditions and reliability |
price_history(model, days | from + to | at, granularity, provider, limit) | Offer price history, plus the lab's official prices |
estimate_cost(model, prompt_tokens, output_tokens, cached_ratio, requests_per_day) | Estimated cost per request and per month, sorted |
Every result includes api_url, the equivalent API call, so you can check or reuse it.
Setup
For Cline and other agents that install servers themselves, see llms-install.md.
Claude Code
With an API key, add --header "x-api-key: YOUR_KEY".
Claude Desktop / claude.ai: Settings → Connectors → Add custom connector, URL https://mcp.inferindex.dev/mcp.
Older Claude Desktop versions, in claude_desktop_config.json:
Cursor: one click, or add it by hand.
In ~/.cursor/mcp.json:
With an API key, add "headers": { "x-api-key": "YOUR_KEY" } next to "url".
Codex CLI
Or in ~/.codex/config.toml:
With an API key, add env_http_headers = { "x-api-key" = "INFERINDEX_API_KEY" } to that table and set the
INFERINDEX_API_KEY environment variable.
Contributing
Documentation fixes and example contributions are welcome — open a pull request or an issue. This repository covers the public API surface only; the backend itself is not open source.
License
- Documentation (this README,
docs/): CC BY 4.0. Reuse and adapt it freely, with credit to InferIndex. - Code (examples, snippets, client SDK): MIT.
These licenses cover this repository only, not the InferIndex backend or its price data.