Overtime Pay Calculator - Overtime, Late-Night & Holiday Wage Premiums (Japan)
Enter your hourly wage plus overtime, late-night (10pm-5am), and statutory holiday hours to instantly calculate the premium wage breakdown and total under Japan's Labor Standards Act Article 37, including the 50%+ premium for overtime beyond 60 hours/month.
Wage premium rates under Labor Standards Act Article 37 (Japan)
The minimum statutory premium rates for overtime, late-night, and holiday work in Japan.
| Category | Premium rate | Applies when |
|---|---|---|
| Overtime (時間外労働) | 25%+ | Work beyond statutory hours (8 hours/day, 40 hours/week) |
| Overtime beyond 60h/month | 50%+ | The portion of monthly overtime exceeding 60 hours (applies to all company sizes since April 2023) |
| Late-night work (深夜労働) | 25%+ | Work between 10pm and 5am (stacks with overtime/holiday premiums if they overlap) |
| Statutory holiday work (法定休日労働) | 35%+ | Work on the mandated weekly (or 4-in-4-weeks) statutory rest day |
| Late-night overtime | 50%+ (75%+ beyond 60h) | Overtime hours that also fall between 10pm-5am (25%+25%, or 50%+25% beyond 60h/month) |
| Late-night statutory holiday work | 60%+ | Statutory holiday hours that also fall between 10pm-5am (35%+25%) |
Source: Japan's Ministry of Health, Labour and Welfare, based on Labor Standards Act Article 37 and its enforcement regulations (as of July 2026).
What premium pay for overtime is
Premium pay for overtime is the wage that Article 37 of Japan’s Labour Standards Act obliges an employer to pay on top of the ordinary wage for work beyond the statutory hours (eight in a day, forty in a week) and for work at night or on a statutory day off. The premium rate differs with the kind of work: at least 25 percent for overtime, at least 35 percent for work on a statutory day off, and at least 25 percent for night work.
Where premiums overlap — overtime at night, or work on a day off at night — the rates must be added together, and since April 2023 overtime beyond sixty hours in a month carries a premium of at least 50 percent for every employer, whatever its size. This tool handles those categories, the adding of rates and the sixty-hour test in one calculation, so nothing slips through as it can in a hand reckoning.
Sources used in this calculation
Statutory figures such as tax and insurance rates come from the public bodies listed below. They change when the law is revised, so please also check the primary source before relying on the result for an important decision.
- Overtime, holiday, and night-shift premium pay rates — Ministry of Health, Labour and Welfare (厚生労働省) Effective from 2023-04 ／ Last checked 2026-09-07
How to calculate overtime pay
- Enter the hourly wage If you are paid by the hour, enter it as it stands. If you are paid monthly, enter the hourly equivalent — the monthly wage divided by your contracted hours.
- Enter the overtime hours Enter ordinary overtime hours, those that do not fall in the night period from 22:00 to 05:00.
- Enter night and day-off hours Where there is overtime at night, work on a statutory day off, or work on a statutory day off at night, enter the hours under each heading.
- Read the result The breakdown of premium pay by category and the total appear in real time as you type.
Tips for getting more out of it
- If you're on a monthly salary, divide it by your contracted monthly working hours to get an hourly rate first — the wage unit converter can do this for you.
- The 50%+ premium for monthly overtime beyond 60 hours has applied to companies of every size since April 2023 — small and mid-sized employers are no longer exempt.
- A "statutory holiday" isn't necessarily a Saturday or Sunday — it's whichever weekly (or 4-in-4-weeks) rest day your employer designates in its work rules, so check your company calendar.
- Late-night hours (10pm-5am) stack with overtime or holiday premiums when they overlap — for example, late-night overtime is 25%+25% = 50%.
- This tool uses the statutory minimum premium rates. If your employment contract or collective agreement specifies higher rates, those take precedence.
Where calculating overtime pay helps
Checking a payslip
Use it when you want to satisfy yourself that the overtime your employer paid meets the minimum premium rates of the Labour Standards Act.
Estimating unpaid overtime
On leaving a job or in a dispute, it gives you a starting point for the rough sum of premium pay that ought to have been paid.
Seeing what passing sixty hours does
When a busy period looks likely to push overtime past sixty hours in a month, work out in advance how much the higher rate on the excess adds.
Checking the excess over fixed overtime pay
Where a workplace pays a fixed overtime allowance, see what must be paid on top when the hours actually worked exceed the hours it assumes.
Terms about overtime pay
- Statutory working hours
- The ceiling on working hours set by the Labour Standards Act: as a rule eight hours a day and forty a week. Work beyond it is overtime and attracts premium pay.
- Statutory day off
- The one day a week (or four days in four weeks) that the Labour Standards Act obliges an employer to grant. The day named in the work rules is not necessarily a weekend, so it does not always mean Saturday or Sunday.
- Night work
- Work in the hours from 22:00 to 05:00. A premium of at least 25 percent is laid down, meant to compensate for the burden of working against the body’s rhythm.
- Premium pay
- The wage paid on top of the ordinary wage for overtime, night work and work on a day off. Article 37 of the Labour Standards Act sets the minimum rates; work rules or a collective agreement may set higher ones.
- Fixed overtime pay
- An arrangement whereby a set amount of overtime pay, assuming a certain number of hours in advance, is built into the basic wage. If the hours actually worked exceed what was assumed, the excess must be paid separately as premium pay.
Frequently asked questions
Side Note — Why does the premium rate change at 60 hours a month?
The 50%+ premium for overtime beyond 60 hours a month was actually introduced back in a 2010 revision to Japan's Labor Standards Act. Small and mid-sized businesses were granted a grace period at the time, so only large companies applied it at first. That grace period only ended in April 2023, making universal enforcement a fairly recent development.
The policy's goal is to make chronic long hours economically unattractive for employers, nudging them to cut overtime rather than pay for it. The 60-hour line sits below the widely cited "karoshi (death from overwork) line" of roughly 80 hours of monthly overtime — the idea being to apply financial pressure before employees ever reach that danger zone.
The late-night premium (10pm-5am, 25%+) rests on different reasoning than the overtime or holiday premiums. Rather than compensating for total hours worked, it compensates for working against the body's natural rhythm — which is why it simply stacks on top of whichever other premium (overtime or holiday) already applies.
This tool's split of the 60-hour excess between regular and late-night overtime is only an approximation based on the ratio of hours you entered — real payroll systems tally each day's hours in sequence to determine the exact split. Confirm the precise figures with your employer's payroll department.