July 4, 2026 · 7 min read
2-Card vs 5-Card Wallets: A Four-Profile Solver Report
We ran the live solver across four stated spending profiles at a 2-card limit and a 5-card limit, then reported the modeled net-value difference.
Original research
Credit card portfolio research
Reproducible questions tested with the same constraint solver and card data that power the optimizer.
Methods, assumptions, and verification dates are documented in each report.
Solver-backed reports
These studies compare modeled portfolios under stated spending profiles and eligibility assumptions. They are evidence about the tested profiles—not universal prescriptions.
Read our model methodology before interpreting the results.
Read report
July 12, 2026 · 8 min read
Do Annual-Fee Cards Actually Out-Earn Free Wallets? We Made the Solver Choose
Four profiles solved twice — full catalog vs $0-fee cards only. Fee cards won by $50.45/year on average; the lightest spender’s optimal fee was $0.
July 12, 2026 · 7 min read
Optimizing Credit Cards as a Couple: One Strategy or Two?
We solved a couple’s cards separately and together. Pooling spend at the same card count earned $98/year more — but merging onto fewer cards lost money.
Run your own profile
A study is a benchmark, not your answer.
Your spending, existing cards, fee tolerance, and reward valuations can produce a different portfolio.