OnSimmer
Card benefits, on autopilot

Use every credit. Keep every card alive.

OnSimmer tracks the perks buried in your annual fees, nudges you before credits expire, and keeps dormant cards open with a tiny charge that goes to charity.

Card numbers are tokenized by Stripe — we never store them.
Portfolio
This period
Annual fees
$1,820
Unused credits
$272
Amex Gold
•••• 1007
Hilton Aspire
•••• 2245
Underwater

Everything your cards earn, in one calm place.

No spreadsheets, no missed credits, no surprise dormancy closures.

Benefit tracking

Check off credits as you spend them and watch each card's utilization climb toward 100%.

Backburner to charity

A tiny recurring donation keeps rarely-used cards open — and does a little good while it's at it.

Annual-fee ROI

See whether each fee is paying for itself — in plain dollars — and decide what's worth keeping.

Stop leaving money on the table.

The average member rescues hundreds in credits they'd have let expire. Setup takes two minutes.