Fits a small envelope
Standard letter
定形郵便物
¥110up to 50 g
- 14–23.5 cm long
- 9–12 cm wide
- Up to 1 cm thick
Japan Postage Calculator
Enter the sealed envelope’s size, thickness, and weight. The domestic letter price updates as you type.
Enter the envelope details
Estimate from the contents or use the exact weight.
Based on current Japan Post rates
No sign-up, no personal data
Exact weight gives the safest result
Japan domestic letter rates
These are the base prices before express, tracking, or registered-mail fees.
Fits most A4 envelopes
Non-standard · standard size
定形外郵便物（規格内）
| Up to 50 g | ¥140 |
|---|---|
| Up to 100 g | ¥180 |
| Up to 150 g | ¥270 |
| Up to 250 g | ¥320 |
| Up to 500 g | ¥510 |
| Up to 1 kg | ¥750 |
Thicker or unusually shaped
Non-standard · oversized
定形外郵便物（規格外）
| Up to 50 g | ¥260 |
|---|---|
| Up to 100 g | ¥290 |
| Up to 150 g | ¥390 |
| Up to 250 g | ¥450 |
| Up to 500 g | ¥660 |
| Up to 1 kg | ¥920 |
| Up to 2 kg | ¥1,350 |
| Up to 4 kg | ¥1,750 |
Which Japanese envelope do I have?
Look for these names on the package in a stationery shop or convenience store.
A4 folded in thirds
長形3号 / Nagagata 3
120 × 235 mm · about 5 g
A4 kept flat
角形2号 / Kakugata 2
240 × 332 mm · about 18 g
A4 close-fit envelope
角形A4号 / Kakugata A4
228 × 312 mm · about 15 g
Why the estimate can change
One A4 sheet is estimated at 5 g and one clear file folder at 26 g. Real materials vary, so a kitchen scale or the post-office counter wins whenever you are close to a limit.
Need speed, tracking, or compensation?
Express
+¥300For letters up to 250 g. The surcharge rises for heavier items.
Tracking
+¥210Records acceptance and provides online tracking. No compensation for loss or damage.
Simple registered
+¥350Tracking plus compensation up to ¥50,000. Hand the item over at a post-office counter.
Common questions
Is postage the same anywhere in Japan?
Yes. The domestic letter rates shown here are nationwide. The destination does not change the price, but size, thickness, weight, and optional services do.
Can I trust the A4-sheet estimate?
Use it as a practical estimate only. Paper stock, envelopes, clips, and folders vary. If the result is near a weight boundary, weigh the sealed envelope or take it to a post office.
Can I put cash in an ordinary envelope?
No. Cash must be sent using Japan Post’s registered cash mail service (現金書留 / genkin kakitome) and its dedicated envelope.
Does this calculate international postage?
No. This calculator covers letters mailed within Japan. International letters use different zones, formats, and rates.