# PlatMath

> PlatMath is an interactive break-even calculator for premium credit cards. Users drag sliders to indicate which annual statement credits they actually use, and the tool shows whether the credits exceed the card's annual fee.

The site is a static single-page application. All card data lives in `data/<card-id>.js` files in the GitHub repository and is updated when issuers change credits.

## Cards covered

- [Amex Business Gold](https://platmath.com/?card=amex-biz-gold): $375 annual fee, up to $845 in annual credits. Source: https://www.doctorofcredit.com/american-express-adds-300-chatgpt-business-credit-to-business-cards-platinum-gold/ (updated 2026-05-14).
- [Amex Business Platinum](https://platmath.com/?card=amex-biz-plat): $895 annual fee, up to $2180 in annual credits. Source: https://www.doctorofcredit.com/american-express-adds-300-chatgpt-business-credit-to-business-cards-platinum-gold/ (updated 2026-05-14).
- [Amex Gold](https://platmath.com/?card=amex-gold): $325 annual fee, up to $424 in annual credits. Source: https://www.doctorofcredit.com/american-express-gold-card-changes-hertz-five-star-status-new-dining-partners-af-remains-same/ (updated 2026-07-19).
- [Amex Platinum](https://platmath.com/?card=amex-platinum): $895 annual fee, up to $3075 in annual credits. Source: https://www.doctorofcredit.com/american-express-to-remove-100-saks-benefit-on-platinum-card/ (updated 2026-05-24).
- [Bilt Palladium](https://platmath.com/?card=bilt-palladium): $495 annual fee, up to $600 in annual credits. Source: https://support.biltrewards.com/hc/en-us/articles/42648880265869-Bilt-Card-2-0-Benefits-Overview (updated 2026-07-04).
- [Chase Sapphire Reserve](https://platmath.com/?card=chase-sapphire-reserve): $795 annual fee, up to $2348 in annual credits. Source: https://www.doctorofcredit.com/chase-sapphire-reserve-enhances-500-the-edit-credit-adds-one-time-250-hotel-credit/ (updated 2026-07-05).
- [Chase Sapphire Reserve Business](https://platmath.com/?card=chase-sapphire-reserve-business): $795 annual fee, up to $2040 in annual credits. Source: https://www.doctorofcredit.com/chase-sapphire-reserve-enhances-500-the-edit-credit-adds-one-time-250-hotel-credit/ (updated 2026-07-05).
- [Citi Strata Elite](https://platmath.com/?card=citi-strata-elite): $595 annual fee, up to $700 in annual credits. Source: https://www.doctorofcredit.com/live-citi-strata-elite-review-80000-points-bonus-595-annual-fee-300-hotel-200-splurge-credit/ (updated 2025-07-27).
- [Delta SkyMiles Platinum](https://platmath.com/?card=delta-platinum): $350 annual fee, up to $890 in annual credits. Source: https://www.americanexpress.com/us/credit-cards/card/delta-skymiles-platinum-american-express-card/ (updated 2026-07-04).
- [Delta SkyMiles Platinum Business](https://platmath.com/?card=delta-platinum-business): $350 annual fee, up to $940 in annual credits. Source: https://www.americanexpress.com/en-us/business/credit-cards/delta-skymiles-platinum/ (updated 2026-07-04).
- [Delta SkyMiles Reserve](https://platmath.com/?card=delta-reserve): $650 annual fee, up to $1360 in annual credits. Source: https://www.doctorofcredit.com/credit-cards/rewards/delta-reserve-credit-card-from-american-express-review/ (updated 2026-07-04).
- [Delta SkyMiles Reserve Business](https://platmath.com/?card=delta-reserve-business): $650 annual fee, up to $1410 in annual credits. Source: https://www.americanexpress.com/en-us/business/credit-cards/delta-skymiles-reserve/ (updated 2026-07-04).
- [Hilton Honors Aspire](https://platmath.com/?card=hilton-aspire): $550 annual fee, up to $1600 in annual credits. Source: https://www.americanexpress.com/us/credit-cards/card/hilton-honors-aspire/ (updated 2026-07-04).
- [Marriott Bonvoy Brilliant](https://platmath.com/?card=bonvoy-brilliant): $650 annual fee, up to $1100 in annual credits. Source: https://www.americanexpress.com/us/credit-cards/card/marriott-bonvoy-brilliant/ (updated 2026-07-04).
- [United Club Business](https://platmath.com/?card=united-club-business): $695 annual fee, up to $890 in annual credits. Source: https://creditcards.chase.com/business-credit-cards/united/united-club-business (updated 2026-07-04).
- [United Club Card](https://platmath.com/?card=united-club): $695 annual fee, up to $890 in annual credits. Source: https://creditcards.chase.com/travel-credit-cards/united/club-infinite (updated 2026-07-04).

## How break-even is calculated

For each card, sum the dollar value of every credit the user marks as "used" (via slider or toggle). If that sum is greater than or equal to the card's annual fee, the card breaks even. The calculator does not include sign-up bonuses, points-earning value, lounge access, Clear/TSA PreCheck/Global Entry, or non-monetary perks.

## Data sources

Card credit data is primarily sourced from Doctor of Credit articles, with each card's exact source URL listed in its data file. The site's authors periodically refresh `last_updated` dates and credit values when card terms change.

## Excluded from calculations

The following perks are intentionally excluded from break-even math because they are non-monetary or vary widely by user: airport lounge access (Centurion, Priority Pass, Sapphire Lounge, etc.), Clear Plus, TSA PreCheck, Global Entry, hotel elite status, sign-up bonuses, and points-earning multipliers.