Japanese Era Names (Gengō): From Meiji to Reiwa

What are Japanese Era Names (Gengō)?

Japan uses era names, called gengō (元号, げんごう, gengō / gengo), alongside the Gregorian calendar. A gengō is used with a year number, like:

Since Meiji (明治), Japan has generally followed a “one reign, one era name” approach (一世一元, issei-ichigen), meaning the era changes when a new emperor ascends the throne.

Key Points to Understand

1. Era changes happen on a specific date (not always January 1)

An era begins on an accession-related date, so the same Gregorian year can contain two eras. For example:

• 2019 includes Heisei until April 30 and Reiwa from May 1
• 1989 includes Shōwa until January 7 and Heisei from January 8

2. The first year may be written as 元年 (gannen)

The first year of an era is often written as 元年 (がんねん, gannen), meaning “the first year.” In modern practice, that first year starts on accession and runs until December 31.

3. Gengō is especially common on official documents

Even if people speak in Western years in casual conversation, you will often see gengō on:

• Government forms and applications
• Driver’s licenses and ID cards
• Official certificates
• Some business paperwork

The Five Modern Eras: Meiji → Reiwa

Understanding Overlap Years

Some Gregorian years contain two era labels. This is the most important concept for English readers:

Quick Conversion Rules

Use these formulas to convert between era years and Gregorian years. Always check the exact date in transition years!

Reiwa (from 2019-05-01)

Heisei (1989-01-08 to 2019-04-30)

Shōwa (1926-12-25 to 1989-01-07)

Taishō (1912-07-30 to 1926-12-25)

Meiji (1868-10-23 to 1912-07-30)

How Dates Look on Japanese Documents

You may see dates written in various formats:

Full era format (very common)

令和6年4月1日

“Reiwa 6, April 1” (i.e., 2024-04-01)

With gannen (first year)

令和元年5月1日

“Reiwa gannen (Year 1), May 1” (i.e., 2019-05-01)

On forms

When filling out Japanese forms, you may need to:

• Select the era name from a dropdown (令和/平成/昭和/etc.)
• Enter the year number (without the era prefix)
• Enter month and day

Frequently Asked Questions

Q1: Why does the era change mid-year?

Because modern era names are tied to imperial reign changes (one reign, one era name), so the change happens on the accession-related date, not on January 1.

Q2: Do Japanese people always use gengō in daily life?

Not always. Many people use Gregorian years in casual speech, but gengō remains common in official and administrative contexts. You’ll see it on government forms, driver’s licenses, and official certificates.

Q3: Is it okay to write “Reiwa 1” instead of 元年?

In English explanation, “Reiwa 1” is clear and correct. On Japanese documents, you may see 元年 (gannen) used for the first year, which is the traditional convention.

Q4: How do I know which era to use for a specific date?

Check the transition dates:

• Before 1989-01-08 → Shōwa
• 1989-01-08 to 2019-04-30 → Heisei
• 2019-05-01 onward → Reiwa

For boundary dates, the exact day matters!

Practical Phrases

For forms and documents

• “Please enter the date in either Gregorian format or Japanese era (gengō) format.”
• “If the form requests an era year, select Reiwa and enter the year number.”
• “Note: Some years include two eras due to an era change on a specific date.”

For casual conversation

• “Japan sometimes writes years using era names like Reiwa or Heisei.”
• “My driver’s license shows the year in the Japanese era system.”
• “I usually think in Western years, but paperwork often uses era years.”

Glossary

Related Pages

• Chinese Zodiac (Eto) — Learn about the 12 animals and 60-year cycle
• Age Calculator — Find your Japanese era year and more