ETF comparison
IWP vs MDY
Both US Mid Cap.
iShares Russell Mid-Cap Growth ETF · State Street SPDR S&P MIDCAP 400 ETF Trust
Holdings overlap
97 positions appear in both funds. Buying equal dollars of IWP and MDY would leave roughly 17.3% of each dollar exposed to the same underlying securities.
Unmatched is the part of a fund's weight the other fund doesn't match: names only it holds, plus any extra weight it puts in names both funds hold.
Side by side
Sub-score comparison
Tracking quality isn't part of the composite — see what we don't score for why.
Cost difference
Expense ratios are effectively identical (0.23% vs 0.23%).
Fee figure is the annual expense charged on $100,000. To see how the gap compounds over a multi-decade holding period, open the cost calculator pre-filled with IWP vs MDY.
Top shared holdings
97 shared in total| # | Holding | In IWP | In MDY | Overlap |
|---|---|---|---|---|
| 1 | ATI, Inc. | 0.73% | 0.75% | 0.73% |
| 2 | MACOM Technology Solutions Holdings, Inc. | 0.70% | 0.64% | 0.64% |
| 3 | XPO, Inc. | 0.64% | 0.62% | 0.62% |
| 4 | Woodward, Inc. | 0.69% | 0.56% | 0.56% |
| 5 | Carpenter Technology Corp. | 0.81% | 0.55% | 0.55% |
| 6 | Lattice Semiconductor Corp. | 0.57% | 0.55% | 0.55% |
| 7 | Burlington Stores, Inc. | 0.54% | 0.50% | 0.50% |
| 8 | Sterling Infrastructure, Inc. | 0.69% | 0.47% | 0.47% |
| 9 | Roku, Inc. | 0.47% | 0.58% | 0.47% |
| 10 | SiTime Corp. | 0.45% | 0.47% | 0.45% |
| 11 | Semtech Corp. | 0.41% | 0.52% | 0.41% |
| 12 | TTM Technologies, Inc. | 0.45% | 0.40% | 0.40% |
Only in IWP
169 total- Datadog, Inc. 2.34%
- Snowflake, Inc. 2.33%
- Cloudflare, Inc. 2.12%
- Teradyne, Inc. 2.07%
- Astera Labs, Inc. 2.02%
- Simon Property Group, Inc. 1.96%
- Comfort Systems USA, Inc. 1.89%
- Robinhood Markets, Inc. 1.75%
- Lumentum Holdings, Inc. 1.67%
- Targa Resources Corp. 1.56%
Only in MDY
304 total- Okta Inc. Class A 1.01%
- U.S. Dollar 0.89%
- nVent Electric plc 0.79%
- TechnipFMC plc 0.77%
- United Therapeutics Corporation 0.67%
- TD SYNNEX Corporation 0.64%
- US Foods Holding Corp. 0.60%
- Tenet Healthcare Corporation 0.60%
- Reliance Inc. 0.59%
- Royal Gold Inc. 0.57%
Related comparisons
More comparisons with IWP
- IWP vs IWF · iShares Russell 1000 Growth ETF 10.8%
- IWP vs IWS · iShares Russell Mid-Cap Value ETF 10.6%
- IWP vs VTI · Vanguard Morningstar Total Stock Market ETF 7.5%
- IWP vs ITOT · iShares Core S&P Total U.S. Stock Market ETF 7.5%
- IWP vs SCHB · Schwab U.S. Broad Market ETF 7.2%
- IWP vs VUG · Vanguard Morningstar Growth ETF 5.6%
More comparisons with MDY
- MDY vs IWM · iShares Russell 2000 ETF 11.0%
- MDY vs IWD · iShares Russell 1000 Value ETF 6.8%
- MDY vs VTI · Vanguard Morningstar Total Stock Market ETF 5.0%
- MDY vs ITOT · iShares Core S&P Total U.S. Stock Market ETF 4.8%
- MDY vs SCHB · Schwab U.S. Broad Market ETF 4.6%
- MDY vs VYM · Vanguard High Dividend Yield Index Fund ETF Shares 4.4%
Percentages are holdings overlap with the named fund.
Open IWP or MDY at a brokerage
Both funds trade commission-free at major US brokerages.
Affiliate links — opening an account through these earns PlainIndex a one-time referral. Scoring is computed before any affiliate consideration; see our methodology and funding disclosure.
Holdings overlap is the sum of min(weight_a, weight_b) over positions
matched on ISIN (CUSIP fallback). Methodology: see
/methodology/.
Comparing two funds doesn't endorse swapping one for the other. Tax-lot history, account type, and personal goals matter — PlainIndex publishes data and methodology, not investment advice.