SiftingIO Crypto Data API

What it is

An API, over REST and a WebSocket stream, that publishes one price per USD-quoted crypto pair, BTCUSD rather than one exchange's BTC-USDT. SiftingIO computes that price itself from centralised-exchange inputs and sells the result, not the exchanges' own ticks. The crypto surface is a latest trade, a top-of-book quote, the previous daily close, an end-of-day bar, gainers and losers, a most-active list, a snapshot of the whole crypto market or of up to 250 named symbols in one call, OHLCV bars at eight sizes from 1m to 1mo, a crypto-to-fiat converter and a WebSocket stream.

The same account and key also open forex, US stocks, commodities, a DEX & DeFi feed and SEC fundamentals, each a separate entitlement with its own price. This card covers the crypto feed and the DEX & DeFi feed, which a crypto developer buys on the same key; the equities side has its own card on StockMarketStack.

The publisher is SaltingIO LLC: "Salting" with an "a", where the brand has "Sifting", and the footer reads "A SaltingIO LLC product". The terms describe it as a Wyoming limited-liability company, give 30 N Gould St, STE R, Sheridan, Wyoming as its registered address, and put the contract under Wyoming law with AAA arbitration in Sheridan County. They also send "parent-company" mail to a separate salting.io address without naming a parent. The site names no person. By the About page's timeline the LLC was formed in 2024 and the platform went live in 2025, crypto and forex first. The GitHub organisation was created on 21 April 2026 and the SDK packages were first published on 24 May 2026. We did not check the company against the Wyoming register.

The technical-signal endpoint is why ai_features reads recommendations. It is named under Limitations. It is not why anyone buys the API: it appears on neither the homepage, the pricing page nor the crypto product page, it has no plan of its own, and the API places no orders. The card judges SiftingIO as a price feed.

Pricing

Crypto is priced per market on a five-step ladder. Month to month: Free $0, Builder $99, Pro $299, Ultra $799, Enterprise quoted. The pricing page opens on the annual toggle, which shows $79, $239 and $639 a month, the roughly 20% the page advertises; the $99 entry price is what the crypto product page quotes. Taxes are extra.

What separates the tiers is quota and speed, not data. Every plan gets the same symbols and the full history; the fair price is pushed at 1 update a second on Free, 4 on Builder, 6 on Pro and 10 on Ultra, with Enterprise uncapped. Free and Builder are hard-capped: past the monthly quota every call is refused with a 429 until the billing period turns. Pro may switch on metered overage, priced between one hundredth and one tenth of a cent per call depending on the market. Add-ons: 1 million extra calls from $79 a month, +200 requests a second from $199 a month on Pro and Ultra, +5 connections and +500 symbols from $59 a month.

Display rights start at Pro. Builder is labelled internal use and personal side projects, so a public app showing these prices needs $299 a month, or $239 billed annually.

DEX & DeFi is a second subscription. It costs $129, $399 and $1,099 a month (annual: $103, $320, $879) and has its own free tier with the same limits. Two or more markets at Pro or Ultra take an automatic 10% off, rising to 25% for all five; Builder is not bundle-eligible.

Payment is card or US ACH through Stripe, and the pricing FAQ says crypto is not accepted for billing. Monthly plans cancel at any time, and annual plans are refundable pro rata within 30 days. Trials are by request and the two pages disagree: the homepage offers 7 days of Ultra after a booked demo, the pricing FAQ a 14-day Pro trial through the contact form.

Data & coverage

Where the price comes from, in the vendor's words. The methodology page describes a pipeline rather than a source list. Venue quotes older than a staleness window are dropped, as are prices more than a fixed fraction from the cross-venue median. Each venue's deviation is scored with a median-absolute-deviation z-score and held in a rolling reputation, and a venue whose price stays flat while the market moves is flagged frozen and excluded. The survivors are combined as a median weighted by traded volume times reputation. The page says admitted sources must share no operator or infrastructure and must carry "meaningful real flow". It publishes the method but not the thresholds, and it names no exchange. Neither does the product page, the docs, the symbol catalogue or the two-page technical evaluation sheet. The 74 venues on the homepage are "across 6 asset classes".

The CEX pages say centralised venues only. The terms and the disclosures page say crypto prices come from "centralized and decentralized venues". Which one is true of BTCUSD is not stated.

The bid and ask are derived, not quoted. Top of book is the fair price plus or minus a half-spread, which is the larger of the venues' weighted quoted spread and their cross-venue disagreement, lightly smoothed, so it cannot cross. The vendor calls it a representative spread and not executable depth. Each tick carries a source, an ingest and a publish timestamp, a consensus value, and a flag that turns "degraded" when fewer sources than the quorum are contributing. In that case the engine keeps publishing from its safest source rather than going silent.

History. The bars endpoint documents 1m, 5m, 15m, 30m, 1h, 1d, 1w and 1mo intervals, with volume in the base asset. Approximate earliest dates: BTC September 2013 (the docs' own error example gives 2013-09-13), LTC January 2014, XRP July 2014, ETH August 2015, ADA October 2017, most newer layer-1 coins 2019 to 2021. The historical pair set is narrower than the live one, and the docs do not publish its size. Weekly bars open Monday 00:00 UTC. Pages are capped at 2,000 bars and must be requested gzipped.

Symbols. Everything is USD-quoted. No USDT-, USDC- or BTC-quoted pair is listed, and the docs do not say how venues that quote against a stablecoin are folded into a USD price.

DEX & DeFi. Live swap prices and pair-level TVL (summed across the pools SiftingIO tracks for that pair, not a protocol's TVL) on Ethereum, Base, Arbitrum, BNB Chain and Polygon. There are also native-coin and ERC-20 balances for one wallet on one chain per call, with no USD value. Historical DEX bars are documented for a single symbol, ETHUSD, from 2021-05-05, and empty intervals are omitted rather than filled. That one symbol is the whole of the "5+ years" the pricing page claims for DEX.

Latency. Median delivery under 100 ms from the vendor's primary regions is the only number published. The REST rate limit is per key.

Integrations

Official SDKs for Python (siftingio on PyPI, 0.2.0, uploaded 2 August 2026), TypeScript (@siftingio/sdk on npm, 0.3.0, also 2 August 2026) and Go (github.com/siftingio/sdk-go). The LICENSE file in each repository is MIT. The vendor says all three are generated from the same OpenAPI 3.1 and AsyncAPI 3.0 specs. The Python repository has commits as recent as 21 October 2026, ahead of its last release.

MCP, two editions. A hosted connector for ChatGPT and Claude signs in with OAuth (market-data:read) and exposes 10 read-only tools, including last_trade, last_quote and crypto_bars. A local server, siftingio-mcp on npm (1.0.2, MIT), runs over stdio or a loopback-only HTTP transport with 36 tools, and there is a Python server too. Every tool call is an ordinary API call against your quota, and results are trimmed at about 60,000 characters.

WebSocket is one connection for every market, a subscribe op with product: "cex" or "dex", and one snapshot tick from cache before the live stream. The server closes a connection after 90 seconds without a client frame, and incoming ticks do not count, so a client has to ping. In snapshot responses prices and sizes come back as strings; in bars they are numbers.

For people who do not write code there is a browser export to CSV or Excel (the latest 24 hours without an account), an Excel add-in and a Google Sheets template. For pipelines the GitHub organisation carries an n8n community node (MIT) and a Postgres wrapper for Supabase (Apache-2.0). FIX 4.4 market data is an Enterprise option, with no order entry.

Limitations

You cannot check the price against a named exchange, because the exchanges are not named. A reader reconciling fills on one venue, or proving to an auditor where a mark came from, gets a method and a consensus value but no source list. The vendor shares "per-venue handling" only in a data sheet under NDA.

No order books, no per-venue tape, no tick history. The crypto surface is a derived top of book and bars. The homepage FAQ promises "tick-level history", but the docs index, 40 endpoints across 12 groups, lists no endpoint that serves it.

Spot only. There are no perpetuals, futures, options, funding rates, open interest or liquidations. The About page lists crypto perpetuals and futures as "next", with no date.

The update rate is a plan setting. One price a second on Free and four on Builder are fine for a portfolio screen and slow for anything that reacts to the book. The methodology page says plainly that this is not a feed for sub-millisecond routing or market making.

The licence is narrower than the marketing. The methodology page lists "settlement & reference rates" among the uses it is built for. Terms §9 forbids creating indices, benchmarks, NAVs or reference rates for anyone else, re-serving stored bars as a dataset in their own right, and fitting a machine-learning model that is offered to outsiders, without written authorisation in the plan or order form. Usage is subject to audit and retroactive fees.

Technical signals. GET /v1/last/signals/crypto/:symbol returns a label from strong_sell to strong_buy, sold in the docs as "decision-ready", and a score from −1 to +1. The label is a tally of buy, neutral and sell votes cast by six oscillators and by simple and exponential moving averages from 10 to 200 periods, on any bar size from one minute to one month. A history endpoint replays it bar by bar with golden-cross, death-cross and MACD-cross events. It shipped on 14 August 2026. The changelog says it describes indicator state and is not advice. The docs gate only stock signals to paid plans, so on crypto it is part of every tier, Free included.

A young operator with no named people. The platform launched in 2025 and its code and packages appeared in 2026. The customer counts on the About page (over 30,000 developers, over 150 businesses) describe what its founders built before SiftingIO, at employers the page does not name.

The pages disagree with one another in small ways. The bars docs cap a page at 2,000 bars while their pagination and performance notes use 5,000. The MCP page lists eight chains, Solana among them, where the DEX product page and WebSocket docs list five EVM chains. The pricing matrix prints "up to 25+ years" of history on every tier, while its own market table gives crypto 10+. The pricing FAQ says every plan gets "the same freshness", which the methodology page's per-plan update rates contradict. Trust the endpoint pages and test the window you need on the free key.

Alternatives

If the point is to know which exchange a price came from, CoinAPI is the opposite design: one symbol scheme over each venue's own tape, order books included, with no free plan. Tardis.dev is the choice for tick-by-tick books and trades replayed from named exchange feeds. CoinPaprika API is the closest like-for-like, an aggregated price per coin with a keyless free plan, but much coarser intraday history. For crypto and forex under one subscription, Massive Crypto API sells the two in one plan. If the aim is a licensed benchmark rate, the use SiftingIO's terms reserve, Coin Metrics sells reference rates and indexes under contract. The rest of the field is in Crypto Market Data APIs.