A Quantitative Developer (C++ / Python) earning the median salary of ¥12.4M in Japan takes home approximately ￥8,795,375/year (￥732,948/month) after national income tax, reconstruction surtax, resident tax, and employee social insurance, using 2026 rates.
2026 median salary for each level in Japan, and what it leaves after national income tax, reconstruction surtax, resident tax, and employee social insurance. Single employee, Tokyo standard rates, under 40. 2026 rates.
| Level | Gross / year | Take-home / year | Per month | Effective rate |
|---|---|---|---|---|
| Junior | ￥8,081,000 | ￥6,008,902￥500,742/mo | ￥500,742 | 25.6% |
| Mid-level | ￥12,200,000 | ￥8,679,136￥723,261/mo | ￥723,261 | 28.9% |
| Senior | ￥16,955,000 | ￥11,293,563￥941,130/mo | ￥941,130 | 33.4% |
| Lead / Principal | ￥22,220,000 | ￥14,243,304￥1,186,942/mo | ￥1,186,942 | 35.9% |
The biggest pay step is Senior to Lead / Principal: ￥5,265,000 more a year before tax, of which ￥2,949,741 reaches take-home. 44% of that raise goes to national income tax, reconstruction surtax, resident tax, and employee social insurance, against an average 33% on the Senior salary, because the extra pay is taxed at the top of your bands rather than spread across all of them.
Around the headline median, the middle half of Quantitative Developer (C++ / Python) salaries in Japan run from ￥11,743,000 to ￥12,893,000 a year, which is ￥8,391,994 to ￥9,114,562 after national income tax, reconstruction surtax, resident tax, and employee social insurance.
The table above uses the Quantitative Developer (C++ / Python) median. Enter your own gross salary below for a precise figure.
Annual take-home
￥8,795,375
Monthly take-home
￥732,948
Effective deduction rate
29.0%
National income tax
￥1,299,489
Reconstruction surtax
2.1% of national income tax
￥27,289
Resident tax
~10% (prefectural + municipal)
￥863,017
Health + pension + employment insurance
￥1,399,829
A Quantitative Developer (C++ / Python) earning the median salary of ¥12.4M in Japan takes home approximately ￥8,795,375 per year (￥732,948 per month) after national income tax, reconstruction surtax, resident tax, and employee social insurance, using 2026 rates.
On a median Quantitative Developer (C++ / Python) salary of ¥12.4M, the effective deduction rate (national income tax, reconstruction surtax, resident tax, and employee social insurance) is 29.0%, leaving ￥8,795,375 as take-home pay.
A senior Quantitative Developer (C++ / Python) in Japan earns a median ￥16,955,000 a year and takes home approximately ￥11,293,563 (￥941,130 per month) after national income tax, reconstruction surtax, resident tax, and employee social insurance, an effective rate of 33.4%.
A junior Quantitative Developer (C++ / Python) in Japan earns a median ￥8,081,000 a year and takes home approximately ￥6,008,902 (￥500,742 per month) after national income tax, reconstruction surtax, resident tax, and employee social insurance, an effective rate of 25.6%.
The biggest pay step is Senior to Lead / Principal: ￥5,265,000 more a year before tax, of which ￥2,949,741 reaches take-home. 44% of that raise goes to national income tax, reconstruction surtax, resident tax, and employee social insurance, against an average 33% on the Senior salary, because the extra pay is taxed at the top of your bands rather than spread across all of them.
Quantitative Developer (C++ / Python) Salary Benchmarks
Full range, city comparisons, seniority bands
Check a job offer
See where an offer sits against the market range
Quantitative Developer (C++ / Python) contractor rates
Compare permanent pay with current contract market rates
Remote vs Hybrid
Is the commute worth it?