ETF comparison
IJK vs MDY
Both US Mid Cap.
iShares S&P Mid-Cap 400 Growth ETF · State Street SPDR S&P MIDCAP 400 ETF Trust
Holdings overlap
224 positions appear in both funds. Buying equal dollars of IJK and MDY would leave roughly 58.0% of each dollar exposed to the same underlying securities.
Side by side
Sub-score comparison
Tracking quality isn't part of the composite — see what we don't score for why.
Cost difference
IJK is 6 bps cheaper than MDY. On a $100,000 position that's about $60/yr more in fees for MDY.
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 IJK vs MDY.
Top shared holdings
224 shared in total| # | Holding | In IJK | In MDY | Overlap |
|---|---|---|---|---|
| 1 | Twilio, Inc. | 1.17% | 0.88% | 0.88% |
| 2 | Carpenter Technology Corp. | 1.20% | 0.82% | 0.82% |
| 3 | Curtiss-Wright Corp. | 1.54% | 0.78% | 0.78% |
| 4 | ATI, Inc. | 1.21% | 0.71% | 0.71% |
| 5 | Woodward, Inc. | 1.31% | 0.69% | 0.69% |
| 6 | MKS, Inc. | 0.67% | 0.68% | 0.67% |
| 7 | XPO, Inc. | 1.40% | 0.67% | 0.67% |
| 8 | Okta, Inc. | 0.82% | 0.66% | 0.66% |
| 9 | United Therapeutics Corp. | 1.57% | 0.65% | 0.65% |
| 10 | MasTec, Inc. | 1.21% | 0.64% | 0.64% |
| 11 | Everpure, Inc. | 1.14% | 0.64% | 0.64% |
| 12 | Illumina, Inc. | 0.62% | 0.79% | 0.62% |
Only in IJK
20 total- BlackRock Funds III 4.65%
- TechnipFMC plc 1.71%
- Casey's General Stores, Inc. 1.65%
- Flex Ltd. 1.48%
- nVent Electric plc 1.17%
- Fabrinet 1.15%
- Jazz Pharmaceuticals plc 0.70%
- TopBuild Corp. 0.60%
- Roivant Sciences Ltd. 0.44%
- RenaissanceRe Holdings Ltd. 0.41%
Only in MDY
177 total- U.S. Dollar 0.84%
- TechnipFMC plc 0.74%
- nVent Electric plc 0.68%
- US Foods Holding Corp. 0.64%
- Reliance Inc. 0.53%
- Roku Inc. Class A 0.52%
- TD SYNNEX Corporation 0.51%
- Fabrinet 0.50%
- Coeur Mining Inc. 0.50%
- Performance Food Group Co 0.49%
Open IJK 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.