Our Indexes

The world's leading
independent volatility indexes.

Five precision-engineered indexes that strip away the distortions of legacy vol measures — giving you a clean, real-time read on what options are actually pricing.

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VolDex®
A better way to measure option volatility
VolDex® focuses on the options that matter most—at-the-money (ATM) options with near-term expirations—giving a cleaner, more accurate view of implied volatility.

By isolating these highly liquid and actively traded contracts, VolDex avoids the distortion caused by less relevant, far out-of-the-money options. The result is a more precise snapshot of market expectations for price movement and investor sentiment—without the noise.
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CallDex®
A clearer signal of bullish sentiment & expected volatility
CallDex® tracks the cost of out-of-the-money call options to gauge market sentiment for the next 30 days. It uses call options that are one standard deviation out-of-the-money to measure what investors are expecting in terms of both volatility and potential price direction.

Higher CallDex values generally suggest traders are anticipating bigger moves or a possible market rally. Lower values indicate a calmer outlook or reduced interest in upside exposure.
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PutDex®
Focused on downside risk pricing
PutDex® delivers a clear, strike-specific measure of implied volatility by concentrating on one key data point: the normalized cost of a 30-day, one standard deviation out-of-the-money (OTM) SPY put option.

This approach isolates the segment of the options market most directly associated with downside protection, removing the noise from less relevant strike prices. The result precisely indicates market sentiment around tail risk, hedging activity, and bearish positioning.

By zeroing in on these put options—widely used by institutional investors to protect against market declines—PutDex offers valuable insight into how much investors are willing to pay to insure against losses over the next month.
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RiskDex®
A Clear Signal of Expected Market Direction
RiskDex® measures investor sentiment by comparing the normalized cost of 30-day, one standard deviation out-of-the-money (OTM) SPY put and call options. This simple ratio reveals whether the market is more focused on downside protection or upside opportunity — offering a direct view of expected equity direction over the next month.

Unlike traditional volatility indexes, which reflect overall price movement, RiskDex highlights directional bias. A rising RiskDex indicates OTM put prices are increasing at a faster rate than OTM call prices and suggests growing concerns about potential declines; a lower reading signals confidence or complacency.

This makes RiskDex a valuable tool for traders and risk managers seeking clarity on where the market thinks it's headed—not just how volatile it might be.
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TailDex®
A smarter signal for downside risk & tail hedging demand
TailDex® measures the price of deep out-of-the-money put options to assess bearish sentiment and demand for tail risk protection over the next 30 days. By focusing on puts that are three standard deviations OTM, it reflects how concerned traders are about a major downside move, often called a 'tail event'.

Higher TailDex values suggest rising demand for crash protection or increased fear of large selloffs. Lower values imply a calmer market tone and less urgency to hedge against tail risk.
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How to Read the VolDex® Term Structure Tool

Product Walkthrough

Free to read

How to Read the VolDex® Term Structure Tool

Seven controls, one curve, thirty seconds to a decision. Here's exactly where to look — and the three misreads that cost people money.

You've read what the term structure is. This is how you operate the live tool. Every element on the screen is there for a reason; below, each one is numbered and explained in the order a working trader actually uses them.

1 2 3 4 5 6 7
TermDex® S&P 500 (SPY)
82.31
▲ +5.22 (+6.77%)
vs prior close
● LIVE
SPYQQQIWM EEMIEFTLT HYGGLDSLVIBITVXX
Compare to Yesterday1 Week Ago1 Month Ago 1 Year Ago06/26/2026 ▦Add Date
Today (intraday) Jun 25, 2026 ✕
19.518.5 17.516.515.5 VolDex 71530 6090120 150180270360 Days to Expiration (spaced by calendar days) Nαtions® Indexes
Updated 11:30 AM CDT

The live VolDex® Term Structure widget, labeled. Numbers map to the guide below. Tenors are spaced by calendar days, so the front weeks sit close together and the long end spreads out. (Shown: SPY, upward-sloping / contango, TermDex® 82.31.)

What every control does

  1. The TermDex® reading. Start here. This single number is the slope of the whole curve. Positive and rising means contango is steepening — calm. A low or negative print means the curve is flattening or inverting. The "vs prior close" change tells you which direction anxiety moved today.
  2. The LIVE badge. Confirms the curve is computing off the live option chain, not a stale snapshot. The "Updated" timestamp at the bottom (callout 7) tells you exactly how fresh.
  3. Underlying selector. Eleven markets — SPY, QQQ, IWM, EEM, IEF, TLT, HYG, GLD, SLV, IBIT, and VXX — equity, rates, credit, gold, silver, bitcoin, and the VIX-futures complex. Click to repoint the entire curve and TermDex reading at that asset. Read several in a row to see whether stress is one market's problem or everyone's.
  4. Compare to. The whole point of the tool. Today's intraday curve is plotted automatically against yesterday's close. Add Yesterday, 1 Week Ago, 1 Month Ago, 1 Year Ago, or any specific date. Shape changes are the signal; a single day's curve in isolation rarely is.
  5. Active date chips. Everything currently plotted, color-coded to the lines. Blue is today's intraday curve; the gold chip is your comparison date. Add up to five. The ✕ removes one.
  6. The curve itself. VolDex (at-the-money implied vol) up the y-axis, Days to Expiration across the x-axis — plotted at ten fixed tenors (7, 15, 30, 60, 90, 120, 150, 180, 270, 360 days) and spaced by calendar days, so the front weeks bunch up on the left and the long end fans out to the right. The shape is the read: sloping up = contango, sloping down = backwardation, a local bump = an event priced into one tenor.
  7. The "Updated" timestamp. Bottom-left, beside the curve — here, 11:30 AM CDT. It stamps exactly how fresh the reading is: the curve recomputes live off the option chain through the session, and this is the last refresh. (Bulk CSV export of an underlying's full history is an Everything-tier feature, not part of this view.)
Do it live

Reading the tool here is free. Running it on your own symbols is the product: ETF Analytics for all ETFs, ETF + Equities to add single names, Everything for full history, CSV & alerts.

See plans →

What to look at first

Read it in this order, every time. TermDex number → direction of today's change → the shape of today's curve versus the comparison curve. Three glances. If TermDex is healthy and steady and today's curve sits on top of yesterday's, nothing has changed and you move on. If TermDex dropped hard and the front of today's curve has lifted away from the comparison line, the market repriced near-term risk overnight — and that's worth the next ten minutes of your attention.

The 30-second routine

Open your underlying. Read TermDex and its change. Glance at the slope. Overlay 1 Week Ago. Ask one question: is near-term risk being bid up relative to the long end, or not? That answer points you at a trade — usually a calendar or diagonal when contango is steep, caution when the front inverts.

Three common misreads

Misread: "VolDex is high, so vol is expensive."
Read it right: Level isn't the signal — slope is. A high curve in clean contango is calmer than a lower curve that just inverted. Always read the shape, not just the height.
Misread: Judging one curve in isolation.
Read it right: A curve only means something against a reference. Overlay yesterday, a week, a year. The tool defaults to a comparison for exactly this reason — use it.
Misread: Treating a local bump as backwardation.
Read it right: A single tenor poking up is an event kink, not a stress inversion. Check what's on the calendar just before that tenor before you react. You can use our "Event Volatility Isolation" tool to learn more about how much of the bump is due to the impending catalyst. TermDex measures the overall slope, so it won't flip negative just because one tenor is rich.

Educational content from Nations Indexes. VolDex® and TermDex® are registered marks of Nations Indexes. The annotated figure is a labeled recreation of the live interface for instructional use. Nothing here is investment advice.

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