💌 Japan Postage Calculator (2024 Rates)

Japan Post (日本郵便) revised domestic postage on October 1, 2024. The biggest changes: a standard letter (定形郵便物) up to 50g now costs a flat ¥110 (previously ¥84 for 25g / ¥94 for 50g), and a postcard (はがき) rose from ¥63 to ¥85. Letter Pack Light and Plus went up to ¥430 and ¥600 respectively.

Working out the correct amount matters because most Japanese mail is paid by stamps (切手) - send too little and the item is returned or subject to surcharge; send too much and you simply waste money. The standard-letter size rule is: length 14–23.5cm, width 9–12cm, thickness up to 1cm. Any envelope outside these limits, however light, is treated as non-standard mail. This calculator covers the everyday categories: standard letters, non-standard (定形外) letters by weight and size rules, postcards, and the popular Letter Pack / Smart Letter products.

Express delivery (速達) adds a fixed ¥300 to standard and non-standard letters. If you are sending money or important documents, note that registered mail (書留) and insurance are not included here; check the Japan Post official rate table for those options. For the destination side of a mailing job, our postal code lookup and address formatter cover the rest of the workflow.

Choose a category, then enter the weight (for letters) or quantity (for postcards and Letter Packs). The calculator looks up the rate in the tables below and adds ¥300 for express if you select it.

For standard letters the 2024 revision removed the 25g/50g split - any standard letter up to 50g is ¥110. Non-standard mail has two size rules: standard size (longest side up to 34cm, width up to 25cm, thickness up to 3cm) and large size (up to 60cm, total girth up to 90cm, up to 4kg). The calculator applies the standard-size table unless you pick the large-size option. Adding two items to one mailing job? The quantity field totals the stamp cost, and the express option adds ¥300 per item. If you are comparing postal costs with product prices, remember our consumption tax calculator for the 10% on shipping from commercial sellers.

1. Pick a category: standard letter, non-standard letter, postcard, Letter Pack, or Smart Letter.
2. For letters, enter the weight in grams and choose standard or large size for non-standard mail.
3. Enter the quantity (how many identical items you are mailing).
4. Tick Express (速達) only for letters if you need same-day priority handling (+¥300).
5. Click Calculate to see the per-item rate and the total stamp cost.

Did Japan Post rates change in 2024?

Yes - on October 1, 2024: standard letter up to 50g went to a flat ¥110, postcards to ¥85, Letter Pack Light to ¥430 and Plus to ¥600. Older stamps issued before the change remain valid but may need topping up.

What is the difference between 定形 and 定形外?

定形 (standard) fits the envelope size limits 14–23.5cm × 9–12cm × up to 1cm and weighs up to 50g. Anything bigger or heavier is 定形外 (non-standard) and costs more from the first gram.

How much is express (速達)?

Express adds ¥300 per letter (both standard and non-standard). It is not available for postcards or Letter Pack products, which already move as quickly as standard first-class mail.

What is the cheapest way to send documents?

A standard letter under 50g at ¥110, or a Smart Letter at ¥210 for A5 up to 1kg. For larger documents with tracking and next-day delivery, Letter Pack Plus (¥600) with signature is very popular.

Are the rates the same everywhere in Japan?

Yes - domestic letter rates are flat nationwide. Only ゆうパック parcel delivery is zone-based, and that product is not covered by this calculator.

Do I need extra postage for a rectangular (kaku) envelope?

If the envelope is larger than the standard letter size limits, it is 定形外 and starts at ¥140 (up to 50g). Many A4 envelopes fall into the 定形外 category even when light.

This tool is for informational purposes only and does not constitute financial advice. Consult a qualified financial professional for advice specific to your situation.

The 2024 revision simplified standard letters to a single ¥110 rate for anything up to 50g - a standard envelope with a few A4 sheets folded twice is normally under 50g. If your item exceeds the standard envelope dimensions (14–23.5cm long, 9–12cm wide, 1cm thick), it becomes 定形外 and costs at least ¥140 even if it weighs little, so checking size rules first often saves money. Postcards are ¥85, but the new-year nengajo cards are ¥85 as well. For thick documents that must arrive quickly, Letter Pack Plus (¥600) is usually cheaper than a large-size letter plus express. Express (速達) applies to letters only, never to postcards or Letter Packs. When you print an address label, keep it inside the address formatter for the correct order, then confirm the code with the postal code lookup.