ETFs · Published August 19, 2026

ETF X-Ray: What's Actually Inside a Fund

By Slowio

An ETF’s name is marketing; its holdings are the product. Two funds with near-identical names can differ completely in sector tilt, country exposure and concentration — and the difference only shows up when the composition is laid out: which sectors, which countries, which ten companies actually dominate the basket.

Below, a full x-ray of one of Europe’s most widely held funds — the iShares Core MSCI World ETF — from sector donut to holdings flow, plus a “fee twin”: a fund with nearly the same exposure at a very different yearly cost.

Charts and figures are computed from Slowio’s data snapshot as of 2026-08-19 and are refreshed when the article is next updated.
Feature spotlight · ETF analysis

X-ray any ETF before choosing it

Two ETFs with near-identical names can hold very different things. The ETF page on Slowio opens one up before it is chosen: what it actually holds, how it spreads across sectors and regions, what it costs each year. Here is that x-ray for one of the largest world ETFs Slowio follows:

VT.US · Vanguard Total World Stock Index Fund
Global Large-Stock Blend · domiciled in United States · USD listing
Donut chart: sector allocation of Vanguard Total World Stock Index Fund — Technology is the largest sector at 31.2% of assets
Vanguard Total World Stock Index Fund — allocation by sector, drawn as the app’s composition donut: Technology leads at 31.2% of assets; the 3 smallest sectors are grouped as Other (8.3%).
Sankey diagram: Vanguard Total World Stock Index Fund flowing into 4 sectors and its 10 largest holdings, led by NVDA at 4.0% of assets
The same page’s flow view — fund to sector to stock for the 10 largest holdings, together 21.2% of assets; band widths are each holding’s share of the fund, and NVDA is the single largest at 4.0%.

Behind the charts, the page condenses the fund facts that take longest to dig out of a factsheet:

0.07%
TER (yearly cost)
$82.0B
Fund size
20.8%
Return 3y ann.
21.2%
Top-10 weight
64.6%
North America
31.2%
Technology

One number in that band deserves a second opinion: the fee. iShares MSCI ACWI ETF (ACWI.US) sits in the same Morningstar category with near-identical regional weights, 67% North America to 65% — yet its yearly cost is 0.32% to 0.07%: 4.6× apart for near-identical exposure. And on the ETF-Compare radar the two are twins on every axis except Cost and Size:

Radar chart comparing Vanguard Total World Stock Index Fund and iShares MSCI ACWI ETF on cost, performance, size, risk-adjusted return, income and quality
The comparison radar from the ETF-Compare page — each axis is a 0–100 score against the full ETF universe Slowio follows. Cost scores the yearly fee; Size the fund’s assets ($33.2B vs $82.0B).

And one step further — the Correlations tab puts Vanguard Total World Stock Index Fund next to the four big asset classes: US equities (SPY.US), long-term Treasuries (TLT.US), inflation-linked Treasuries (TIP.US) and gold (GLD.US). Over 180-day returns since 2009, the tightest link is VT.US–SPY.US at +0.96; against gold it drops to +0.21.

Chart matrix: pairwise 180-day return scatters, histograms and correlation values for VT.US, SPY, TLT, TIP and GLD
Every pair — scatter below the diagonal, return histograms on it, correlation above: 4,384 overlapping 180-day observations, 2009–2026, each series in its listing currency.
Scatter chart with marginal histograms: VT.US versus SPY.US 180-day returns with regression line
The tightest pair up close — VT.US versus SPY.US — with the return distributions on the margins; the dashed line is the fitted trend.

The tightest link above — +0.96 against US equities — is the x-ray in one number: with North America at 65% of assets, a world fund largely moves as a US fund.

The same page adds performance and risk tabs, cost analysis, and a “find similar ETFs” search — one URL per fund, for any ETF Slowio follows.

X-ray this ETF →

Slowio is an educational research tool, not financial advice. Figures are computed from Slowio’s data snapshot at build time and may not reflect the latest market data — nothing in this email is a recommendation to buy or sell any security. Do your own research.

Create a free Slowio account →

Run the same analysis on any of the 9,000+ companies Slowio follows — free, no card required.