USPS容積重量計算ツール
USPSのサイズ規定や容積重量ルールに基づく重量算出。
Rules updated for 2026
Live calculator
CALCULATES LOCALLY · NO UPLOAD 容積重量および請求重量の計算
梱包後の外寸を入力してください。数値変更と同時にリアルタイムで計算されます。
概算請求重量
容積重量 (DIM)
実重量（秤計測）
梱包容積
重量差
請求基準
荷物の寸法と重量を入力してください。
容積-
係数単位in³/lb
計算方法と数式
The 2026 rule applies to listed services including Priority Mail Express, Priority Mail, Ground Advantage, and Parcel Select. Verify the DMM for your mailpiece.
FORMULA
USPS DIM weight = Rounded cubic inches ÷ 139 (when volume exceeds 1,728 in³)
The 2026 rule applies to listed services including Priority Mail Express, Priority Mail, Ground Advantage, and Parcel Select. Verify the DMM for your mailpiece.
Worked example
USPS threshold and new divisor
- 1.20 × 14 × 10 = 2,800 in³, above 1 ft³
- 2.2,800 ÷ 139 = 20.14 lb
- 3.Round up: 21 lb DIM weight
Before July 12, 2026, divisor 166 would have produced 17 lb after rounding; the updated divisor produces 21 lb.