Trip Cost Calculator

"Should I pay cash or use points?" answered with math.

Compares the true cost of booking with cash versus each available points currency, accounting for transfer ratios, taxes/fees, and the opportunity cost of burning your points.

No API key needed. Uses local JSON data files plus flight/hotel search results.

Data Files

When to Use

• User has both cash prices (from Duffel/Ignav/Google Flights) and award prices (from seats.aero)
• User asks "should I pay cash or use points?"
• User wants to know the CPP of a specific redemption
• User is deciding between multiple booking strategies for a trip

Core Concepts

Cents Per Point (CPP)

The value you're getting per point when redeeming:

cpp = (cash_price - taxes_on_award) / points_needed × 100

A CPP above the floor valuation from points-valuations.json means you're getting above-average value. Below floor = poor redemption.

Opportunity Cost

Points have value even when unspent. Burning 100K Chase UR at 1.7 cpp (floor) means you're "spending" $1,700 in future travel flexibility:

opportunity_cost = points_needed × floor_cpp / 100

If the cash price is lower than the opportunity cost, pay cash. If higher, use points.

The Decision Framework

IF cash_price < opportunity_cost → PAY CASH (points are worth more saved)
IF cash_price > opportunity_cost → USE POINTS (good redemption)
IF cash_price ≈ opportunity_cost → PAY CASH (preserve flexibility)

The tie goes to cash because points maintain optionality.

Workflow

Step 1: Gather Prices

Cash prices (use one or more sources):

Duffel API → exact bookable fares
Ignav API → fast comparison prices
Google Flights → browser-based, includes Southwest

Award prices (use seats.aero):

Seats.aero API → cached availability across 25+ programs
Seats.aero web → live search (local Patchright only)

Step 2: Calculate CPP for Each Award Option

For each award option with a corresponding cash price:

cpp = (cash_price_usd - award_taxes_usd) / award_miles × 100

Award taxes come from seats.aero trip details (TotalTaxes field, in cents) or estimate $5.60 per segment for domestic US, $50-$200 for international (varies wildly by carrier and routing).

Step 3: Factor in Transfer Ratios

If using transferable points (Chase UR, Amex MR, etc.), the effective points cost changes:

effective_points = award_miles / transfer_ratio
effective_cpp = (cash_price - award_taxes) / effective_points × 100

Example: Flying Blue award at 50,000 miles via Capital One (1:1):

• Effective points: 50,000
• Cash price: $1,200, taxes: $100
• CPP: ($1,200 - $100) / 50,000 × 100 = 2.2 cpp

Same award via Emirates (Capital One 4:3 ratio):

• Would cost 72,500 / 0.75 = 96,667 Cap One miles. Not even comparable.

Step 4: Compare Against Valuations

Load valuations from points-valuations.json:

jq -r '.credit_card_points.chase_ultimate_rewards | "Chase UR: floor \(.floor)cpp, ceiling \(.ceiling)cpp"' data/points-valuations.json

Step 5: Present Comparison

Always use markdown tables.

Flight: SFO → NRT Business Class, Aug 15

Recommendation:

• Best value: Virgin Atlantic at 7.62 cpp, but $200 in taxes and must call to book.
• Best convenience: Aeroplan at 5.44 cpp, bookable online, low taxes.
• Cash price ($4,200) vs opportunity cost ($893-$1,496): Points win decisively. Use points.

Step 6: Round-Trip and Multi-Segment

For round trips, calculate each direction separately. Award pricing is usually one-way, cash pricing is often round-trip. Make sure you're comparing apples to apples:

If cash = round-trip $4,200:
  Compare against: outbound award + return award
  e.g., 75K out + 75K return = 150K total vs $4,200 cash
  CPP = ($4,200 - $240 taxes) / 150,000 = 2.64 cpp

jq Recipes

Get floor valuation for a currency

jq -r '.credit_card_points.chase_ultimate_rewards.floor' data/points-valuations.json

Calculate opportunity cost

# 75,000 Chase UR points
POINTS=75000
FLOOR=$(jq -r '.credit_card_points.chase_ultimate_rewards.floor' data/points-valuations.json)
echo "$POINTS points × $FLOOR cpp = \$$(echo "$POINTS * $FLOOR / 100" | bc) opportunity cost"

Full comparison for one route

# Cash: $4200 round trip. Award: 75000 Aeroplan each way, $120 taxes each way.
CASH=4200
MILES_ONEWAY=75000
TAXES_ONEWAY=120
TOTAL_MILES=$((MILES_ONEWAY * 2))
TOTAL_TAXES=$((TAXES_ONEWAY * 2))

echo "Cash: \$$CASH"
echo "Award: $TOTAL_MILES miles + \$$TOTAL_TAXES taxes"
echo "CPP: $(echo "scale=2; ($CASH - $TOTAL_TAXES) / $TOTAL_MILES * 100" | bc)"

# Opportunity cost at floor valuation
FLOOR=$(jq -r '.credit_card_points.chase_ultimate_rewards.floor' data/points-valuations.json)
echo "Opportunity cost: \$$(echo "scale=0; $TOTAL_MILES * $FLOOR / 100" | bc)"

Hotel Comparison

The same framework works for hotels:

hotel_cpp = (cash_rate_per_night × nights) / total_points × 100

Hotel redemptions vary more than flights. Use points-valuations.json hotel section:

• Hyatt: floor 1.4 cpp (consistently best hotel currency)
• Hilton: floor 0.4 cpp (high point costs, low per-point value)
• Marriott: floor 0.6 cpp

For premium hotel programs (FHR, THC, Chase Edit), factor in the additional benefits (breakfast, upgrade, credit, late checkout) when comparing cash vs points. A $500/night FHR rate with $100 breakfast credit and potential suite upgrade might be worth more than the sticker price.

Chase Travel Portal vs Transfer

Chase Sapphire Reserve gives 1.5 cpp in the Chase travel portal (pay-with-points). This sets a floor:

If award CPP < 1.5 → book through Chase portal instead (guaranteed 1.5 cpp)
If award CPP > 1.5 → transfer to partner (better value)

Amex has a similar portal option at lower rates (0.7-1.0 cpp depending on card). Capital One portal gives 0.75-1.0 cpp.

Common Pitfalls

• Ignoring taxes/fees on awards. Some airlines (especially BA, Lufthansa, Singapore on own metal) add $500+ in fuel surcharges to award tickets. Always subtract taxes before calculating CPP.
• Comparing one-way award to round-trip cash. Make sure denominators match.
• Forgetting transfer ratios. 50K miles via Amex → Emirates at 5:4 costs 62,500 MR, not 50,000.
• Not checking portal pricing. Sometimes Chase/Amex portal pricing beats the transfer math.
• Over-optimizing small differences. If two options are within 0.5 cpp of each other, pick the one with better routing, lower taxes, or more flexibility.

Notes

• Point valuations are subjective. The floor from points-valuations.json is the most defensible number.
• "Opportunity cost" assumes you WILL use those points eventually at floor value. If you're sitting on a huge balance with no plans, the real opportunity cost is lower.
• Currency devaluation risk matters for long-term holdings. Points are depreciating assets.
• Transfer bonuses can shift the math significantly. A 30% bonus on Chase → Flying Blue means 75K UR becomes 97.5K Flying Blue miles.