Product note · Japan × US39.6% cheaper in Japan
Is Kobayashi Menstrual Stain Removal & Antibacterial Laundry Detergent for Women's Underwear 120ml cheaper in Japan? the US vs Japan, a US$1.94 gap | 2026 price check
Cheaper in Japan by US$1.94 (39.6%): Japan ¥450 ≈ US$2.95, the US US$4.89.
01 · Verdict
39.6% cheaper in Japan- Japan list price
- ¥450tax basis not stated · cross-border online store displayed price (JPY; price for Taiwan delivery address, tax basis not stated) · Listed
- Converted US currency
- ≈ US$2.95JPY/USD 0.006564 · Bank of Taiwan board
- US list price
- US$4.89excl. tax · Current US retailer price · In stock
- cheaper in Japan
- US$1.9439.6% · US list price as denominator
US stickers exclude state and local tax; Japan stickers include tax. The bases differ, so this is not a landed cost.
Japantax basis not stated、the USexcl. tax; where the tax basis differs, only the list prices are compared; a comparison of two named sources’ list prices, before card fees, shipping and tax refunds. Checked 2026-09-22. Before you order, use theJapan source page and the US source pagecurrent prices.
Japan vs US price table
| Market | List price | Source · checked | Tax basis · stock |
|---|---|---|---|
| Japancross-border online store displayed price (JPY; price for Taiwan delivery address, tax basis not stated) | ¥450 | Don Quijote Cross-Border Store ↗ | tax basis not statedListed |
| USCurrent US retailer price | US$4.89 | Yui Mart (New York) ↗ | excl. taxIn stock |
| Japan convertedJPY/USD 0.006564 (JPY/TWD 0.2076 ÷ USD/TWD 31.625) | US$2.95 | Bank of Taiwan rate ↗ | Spot sellingNot a card or cash rate |
| Gapcheaper in Japan | US$1.94 | 39.6%US list price as denominator | Extra fees not includedCard fee, shipping and tax-free extra |
To use your own FX, fees and shipping, open the Price calculator.
Is it worth buying in Japan?
Japan ¥450, Taiwan NT$199; both are same-day price snapshots taken when checked, excluding shipping, tax refunds, and card fees.
- With a 1.5% foreign card fee: Japan comes to about US$3.00, still below the US by US$1.89.
- Break-even rate 0.0109 USD/JPY: above it the the US sticker is the cheaper one (this check used 0.0066, cross-converted from the Bank of Taiwan yen and dollar rates).
Before you buy
- Only paired when capacity, pack count, and main-unit/refill status match; differences in color, retailer, or stock do not affect the same-product determination.
- The Taiwan price is a retail-channel list price (which may be an authorized import, a parallel import, or a cross-border storefront), not the brand's official price.
- Price and stock follow the page on the day of verification.
05 · Sources
Each price keeps its source link, price kind, tax basis and check date, and is calculated with the TravPrice comparison method. If a price or model is wrong, check the source page and report it.
- Japan price
- Don Quijote Cross-Border Store ↗cross-border online store displayed price (JPY; price for Taiwan delivery address, tax basis not stated) · tax basis not stated · Listed · checked 2026-09-11
- US price
- Yui Mart (New York) ↗Current US retailer price · excl. tax · In stock · checked 2026-09-22
- FX
- Bank of Taiwan FX ↗Bank of Taiwan spot selling reference rate; the US dollar is cross-converted · JPY/USD 0.006564 (JPY/TWD 0.2076 ÷ USD/TWD 31.625) · 2026-09-10 23:22:00 (Taiwan time)
- Model match
- Japan ranking title: 120ml; a separate source category field says 100g per bottle; JAN 4987072066447. Taiwan product page: 120ml. Paired as one 120ml bottle using the product name and matching JAN on the Japan and US product pages.The brand (Kobayashi Pharmaceutical), purpose (laundry detergent for women's period underwear), and volume (120ml) match exactly. Root re-verification: momo product page re-check: Kobayashi Pharmaceutical Period Laundry Detergent 120ml, NT$199. The Japan listing's product name states 120ml (the source's category field separately states 100g; the 120ml in the product name governs), so both sides are 120ml.
- Official product page
- Brand product page ↗Product images on this site are redrawn illustrations; use the official page for appearance, extras and packaging.
- This page generated
- Generated from the same checked data; it is recalculated when the data updates.
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