The real cost of exchanging money shows up in the gap between the buy rate and the sell rate, not in the commission. That gap is the shop’s margin, so a shop with no commission but a wide gap can still cost you more.

If a shop buys USD at 150 yen and sells at 158 yen, the gap is 8 yen. If another shop’s gap is 5 yen, that shop is better. This single number is what to compare.

1. Look at the buy and sell rate for the same currency on the shop’s board
2. Subtract: sell minus buy (e.g. 158 − 150 = 8 yen)
3. Do the same at another shop and pick the smaller gap

This is more reliable than claims like “no commission” or “best rate guaranteed”. The larger the amount you exchange, the more the gap matters.

• Airports — convenient on arrival, but the gap tends to be wider
• Banks — limited counter hours, and fees weigh more on small amounts
• City exchange shops — gaps vary a lot; always check the board
• ATM with a foreign card — your card issuer adds its own fee on top

These are general tendencies. Actual numbers differ shop by shop, so run the three steps above on the spot.

We are a 4-minute walk from the Electric Town Exit of Akihabara Station, on the 1st floor of Don Quijote Akihabara. Open 10:00–19:00, every day of the year. No appointment needed.