Real-time vs delayed market data

What real-time and delayed data mean

Real-time data is delivered as fast as the system can carry it. In the FinaQuotes feed a tick is delivered within a fraction of a second after the price is received from the source. Nothing holds it back on purpose.

Delayed data is the same price stream released after a deliberate, fixed lag. A price that was formed at 14:00:00 is shown at 14:15:00 when the delay is 15 minutes. The data is still accurate for its time; it is simply not current.

Two other ideas are often confused with delay. Refresh rate is how often an interface redraws: a widget that updates every 5 seconds shows the newest price it has at each redraw, which can still be real-time data. Staleness is when no new price has arrived at all, for example because a market is closed. Neither is the same as a delay applied by policy.

Where the 15-minute rule comes from

Exchanges treat the prices produced on their venues as a product. Real-time exchange data is typically distributed under licence, with fees, usage reporting and rules about who may see it and how it may be displayed. Delayed data, after a set interval has passed, is commonly treated as less sensitive and is available for wider display, for example on public websites.

Fifteen minutes is the most widespread delay used for this purpose, which is why it appears on so many quote pages. It is a market convention rather than a universal law: the rules differ between exchanges and between types of use, and they change over time.

This guide describes general practice only. It is not legal advice and does not describe the terms of any specific exchange. If you redistribute market data, check what your agreement with your provider allows, and take your own legal advice where needed. The market data policy explains the terms that apply to FinaQuotes data.

Not every asset class works this way. Forex and spot metals are dealer markets without a single exchange that owns the price, and crypto trades on many independent venues. Prices in these markets are widely shown in real time.

What is real time and what is delayed in FinaQuotes

In the FinaQuotes feed, US stocks are real time, with trades and quotes. Crypto, forex, metals, commodities, indices and bonds are also delivered in real time. Non-US stocks are delayed by about 15 minutes.

Widgets follow a separate rule, because they are designed to be placed on public pages.

• Free widgets show crypto, forex and metals in real time. Exchange-traded instruments, meaning stocks, indices, commodities and bonds, are shown with a 15-minute delay. A delayed price is always shown as a single price: bid = ask = last. Free widgets redraw every 15 seconds.
• Pro widgets show data the way the feed delivers it: real time for every asset class, except non-US stocks, which keep their feed delay of about 15 minutes. They redraw every 5 seconds and are installed natively on your site, without an iframe.

The 5-second and 15-second figures are refresh rates of the widget interface, not data delays. A Pro widget that redraws every 5 seconds shows real-time data; a Free widget that redraws every 15 seconds shows real-time forex next to stock prices that are 15 minutes old. Details per widget are on the widgets page, and the full coverage is on the coverage page.

When a delay is acceptable and when it is not

The question to ask is simple: will anyone act on this price within the next few minutes?

• Acceptable: a news or content site that shows market levels next to articles, a market overview on a blog, an educational page, a newsletter, a long-term chart. Readers want context, not a price to trade at.
• Acceptable with care: a portfolio page that shows end-of-day values or long-term performance, as long as the delay is labelled.
• Not acceptable: a broker platform or trading terminal, where clients place orders at the prices on screen. Prices there must be real time, and the feed must keep running when a source fails; see market data for brokers.
• Not acceptable: price alerts, risk monitoring, any pricing logic and anything that compares a price with the current market.

If a site needs real-time prices for some instruments but not others, mixing is fine, as long as each price is labelled. That is exactly what the Free widgets do with real-time crypto and forex and delayed exchange-traded instruments.

How to show a delay honestly

A delayed price shown without a label looks like a current price. Users who notice the difference stop trusting the page; users who do not notice may make decisions on old data. A few small habits avoid both.

• Put the label next to the price, not in a footer: for example "Delayed 15 min" or a small clock icon with a tooltip.
• Label per instrument when a table mixes real-time and delayed rows.
• Show the time of the last update in the user time zone, so that a closed market is not mistaken for a frozen page.
• State once on the page that prices are indicative and are not investment advice.
• Do not present a delayed single price as a two-sided quote. With bid = ask = last, show one price.

Choosing between Free, Pro and the feed

For a content site that only needs context, Free widgets are often enough: they are free, need no account and are configured in the builder on the widgets page. For a site that needs real-time data on every asset class, white-label design or a faster refresh, Pro widgets fit better. For a broker or a platform that builds its own interface, the feed itself is the right tool: WebSocket for live ticks and REST for history, documented in the documentation. Prices for the feed and Pro are on request; see pricing.

Frequently asked questions