Japanese Content-Certified Mail (Naiyo Shomei) Maker | Check Characters per Line and Lines per Page (Vertical 20×26, Horizontal 20×26, 13×40, 26×20), Print on an A4 Grid, Count Pages and Calculate the Fee with Certificate of Delivery, Sample Demand Letters
The Content-Certified Mail Maker helps you prepare a naiyo shomei letter yourself, the Japan Post service that certifies what you sent, to whom and when. A content-certified letter must fit one of the fixed layouts: vertical writing with up to 20 characters per line and 26 lines per page, or horizontal writing with 20 characters × 26 lines, 13 characters × 40 lines or 26 characters × 20 lines. Enter the body, the date and the sender's and recipient's names and addresses, and the tool places them one character per square in the layout you chose, moves characters so that a line never starts with a comma or full stop, and shows the number of pages, the lines used and how many lines are left on the last page. It also shows how many pages the other layouts would take, so you can pick the one that needs the fewest sheets (and costs least). It warns you about Latin letters, emoji, combined characters such as ㈱ and half-width katakana. The result prints on A4 with the grid aligned, one page per sheet, either once or as the three copies you hand in at the counter. The fee breakdown adds the basic postage, registered mail, the content certification fee (¥480 for the first page and ¥290 for each additional page), certificate of delivery and express delivery, with a quick table for 1 to 10 pages. The text of the letter itself stays in Japanese, and sample letters and the steps for sending one at the post office are included.
Page layout
A content-certified letter has a fixed number of characters per line and lines per page. There is one vertical layout and three horizontal layouts to choose from.
Write the letter
Write the letter in Japanese. To indent a paragraph by one character, type a full-width space. You can insert a sample from “Samples & how to send”.
Date style
令和 年 月 日
The sender and recipient written on the envelope must match those in the letter. For a company, write it like 「○○株式会社 代表取締役 ○○○○」 (company name, representative director, name).
Character and line check
Pages
1 p.
Lines used
2 lines
Left on the last page
24 lines
Characters (excluding spaces)
5 characters
Estimated fee at the post office: ¥1,420 (1 pages, with certificate of delivery)
Vertical, 20 characters × 26 lines: 1 p. ／ Horizontal, 13 characters × 40 lines: 1 p. ／ Horizontal, 26 characters × 20 lines: 1 p.
Punctuation and symbols count as one character, and opening and closing brackets are counted separately. The post office counts a pair of brackets as one character, so this is slightly stricter than the counter (if it fits here, it will always fit).
Preview
One character per square. It prints on A4 exactly like this.
Print on A4
Prints one page per sheet with the grid aligned. Take three identical copies to the counter (for the recipient, for you and for the post office).
If there are two or more pages, staple them and stamp the sender's seal across each join (keiin). Bring the seal to the counter too, as you need it for any corrections made there.
ABOUT
About Japanese Content-Certified Mail (Naiyo Shomei) Maker | Check Characters per Line and Lines per Page (Vertical 20×26, Horizontal 20×26, 13×40, 26×20), Print on an A4 Grid, Count Pages and Calculate the Fee with Certificate of Delivery, Sample Demand Letters
The Content-Certified Mail Maker lays out the text of a Japanese naiyo shomei letter one character per square in the fixed limits (vertical 20 characters × 26 lines, or horizontal 20×26, 13×40 or 26×20), and shows how many pages it takes and how much it costs to send. It prints on an A4 grid, flags characters that are not allowed, and includes sample letters and the steps for sending one at the post office.
How to use Japanese Content-Certified Mail (Naiyo Shomei) Maker | Check Characters per Line and Lines per Page (Vertical 20×26, Horizontal 20×26, 13×40, 26×20), Print on an A4 Grid, Count Pages and Calculate the Fee with Certificate of Delivery, Sample Demand Letters
- 1Under “Page layout”, choose vertical 20×26 or horizontal 20×26, 13×40 or 26×20
- 2Enter a heading (such as 通知書 or 請求書) and the body. To use a sample, insert it from “Samples & how to send” and replace the ○○ parts
- 3Enter the date and the sender's and recipient's names and addresses (they are added at the end automatically)
- 4Under “Character and line check”, confirm the page and line counts and that there are no warnings about characters
- 5Choose whether to print the grid lines and page numbers, then press “Print” to print on A4 and prepare three copies
- 6Under “Fee calculator”, choose certificate of delivery or express delivery and check the amount to pay at the counter
Great for
- Prepare a content-certified letter demanding repayment of a loan or unpaid wages and send it yourself
- Check whether a letter written in Word fits the naiyo shomei character and line limits
- Compare whether the 26×20 or 13×40 horizontal layout needs fewer pages
- Print a cooling-off or contract cancellation notice in the required format
- Find out in advance what a two- or three-page letter costs with certificate of delivery
- Check what to bring to the counter (three copies, an envelope, a seal) and how to make corrections
Good to know
- A content-certified letter must use one of these limits: vertical writing with up to 20 characters per line and 26 lines per page, or horizontal writing with up to 20 characters × 26 lines, 13 characters × 40 lines or 26 characters × 20 lines. The paper size and type, and whether it is handwritten or printed, are up to you.
- Punctuation and symbols count as one character each. The post office counts a pair of brackets as one character, but this tool counts the opening and closing bracket separately, so it is slightly stricter than the counter. If it fits here, it will always fit.
- Latin letters may be used only for proper nouns such as company or product names. Emoji and combined characters such as ㈱ display differently on different computers, so writing （株） instead is safer.
- Fees are Japan Post's rates revised on 1 October 2024 (unchanged as of October 2026): basic postage ¥110 for a standard-size letter, registered mail ¥480, content certification ¥480 for the first page and ¥290 for each additional page, and certificate of delivery ¥350. One page with certificate of delivery comes to ¥1,420.
- The weight assumes about 4 g per sheet of A4 copy paper and about 5 g for a Naga-3 envelope, counting only the recipient's copy that goes in the envelope. Over 50 g, non-standard-size rates apply.
- At the counter you need three identical copies (for the recipient, for you and for the post office), an envelope with the same sender and recipient names and addresses, and your seal. If the letter has two or more pages, bind them and stamp your seal across each join.
- The samples are general examples, not legal advice. The text and addresses are saved only in this browser and never sent to a server (you can also turn saving off).
Questions this tool answers
Use Japanese Content-Certified Mail (Naiyo Shomei) Maker | Check Characters per Line and Lines per Page (Vertical 20×26, Horizontal 20×26, 13×40, 26×20), Print on an A4 Grid, Count Pages and Calculate the Fee with Certificate of Delivery, Sample Demand Letters for searches like these:
- What are the character and line limits for Japanese content-certified mail?
- Does my letter fit the naiyo shomei 26×20 layout?
- How do I print a naiyo shomei letter on a character grid?
- How many pages will my content-certified letter be, and how much will it cost?
- How much is content-certified mail with certificate of delivery?
- Sample naiyo shomei letter for an unpaid loan or unpaid wages
- What do I need to bring to the post office to send naiyo shomei?
FAQ
- How many characters per line and lines per page are allowed in naiyo shomei?
- For vertical writing, up to 20 characters per line and 26 lines per page. For horizontal writing you can choose up to 20 characters × 26 lines, 13 characters × 40 lines or 26 characters × 20 lines. These are maximums, so fewer characters or lines are fine. When you choose a layout in this tool, it places your text on a grid of that size.
- Do punctuation marks and brackets count as characters?
- Commas and full stops (、。) and symbols such as ・ and ％ each count as one character. A pair of brackets such as 「」 or （） counts as one character. To be safe, this tool counts the opening and closing bracket separately, so anything that fits here will also fit at the counter.
- How much does content-certified mail cost?
- For one page in a standard-size envelope: basic postage ¥110 + registered mail ¥480 + content certification ¥480 = ¥1,070, or ¥1,420 with certificate of delivery (¥350). Each additional page adds ¥290 to the certification fee, so two pages with certificate of delivery cost ¥1,710 (rates revised in October 2024).
- How many copies do I need?
- Three identical copies: one sent to the recipient, one you keep and one kept by the post office. You can print one and photocopy the other two, or print all three at once with this tool.
- What should I do if the letter runs to two or more pages?
- Bind each of the three copies with a staple or similar, and stamp the sender's seal across the join between pages (keiin). This tool can print page numbers at the bottom of each sheet so the order is clear.
- How do I correct a mistake?
- Strike through the wrong characters with a double line, write the correct ones, note in the margin how many characters were deleted and added (○字削除, ○字加入) and stamp the sender's seal. If you made the letter on a computer, it is more reliable to fix it and print again.
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