That 6% crypto card is probably paying you 1.8%
Crypto cards advertise 4%, 6%, even 20% cashback. The headline is real — the catch is everything around it: token staking requirements, reward caps, and rewards paid in a volatile token. This calculator computes your effective rate, the only number that matters.
Effective rate calculator
Effective cashback
Hidden costs
Card terms
The math, line by line
1 · Cap the rewards. Rewards = min(spend × rate, cap). At $1,500 spend and 6%, that's $90 — but a $50 cap keeps $50. Your rate is already down to 3.3%.
2 · Charge for the lockup. Staking $4,000 of the card's token means giving up ~4.5%/yr you could earn in a boring treasury fund: $180/yr of opportunity cost.
3 · Mark the stake to market. If the token drops 20% in a year, your $4,000 stake loses $800 — more than the $600 of capped rewards you earned.
effective = (rewards×(1+tokenΔ/2) − stake×4.5% + stake×tokenΔ) ÷ spendRewards also arrive in the token, so they ride half the year's price change on average — that's the (1+Δ/2) term. Net result for the example card: ≈ −$380/year, an effective rate of −2.1%. The same person with a plain 2% no-annual-fee card: +$360, guaranteed.
Four checks before you apply
Rate on what tier?
The advertised rate usually requires the top staking tier. Find the rate at the tier you'd actually hold — often 1–2% at zero stake.
Cap and exclusions
Caps ($25–$100/mo is common) plus excluded categories (rent, groceries at wholesalers, top-ups) can halve real rewards. Read the exclusion list, not the banner.
Reward token liquidity
Can you auto-sell rewards to stablecoin or fiat instantly, and at what spread? Rewards you can't exit cheaply aren't cashback — they're airdrops with homework.
Benchmark: boring 2%
A fee-free 2% card with no conditions is the number to beat. If the crypto card's effective rate under YOUR spend doesn't clear it, the decision is made.