Proportion Calc Downloads & RevenueProportion Calc · App Store
比例・法長計算
Proportion Calc is #130 in Business Paid in Japan and charting in 1 of 30 countries we track.
Updated 8 Nov 2026 · rankings refresh through the day
Developeryouji okamura
CategoryBusiness
Price300 JPY
Released
Rating★ 5.0 (1)
Version2.0
Age rating4+
First seen by us
6 Nov 2026
6 Nov 2026Full timeline · 4 events
- 🆕Proportion Calc first spotted by AppInsider#29 in Top Paid · Business · Japan
- 📦Proportion Calc version 2.0Redesigned the calculation screen to show diagrams, inputs, and results together.
Updated the forward and reverse calculation workflow and triangle diagrams. Added result copying, local calculation history, input validation, Dark Mode, and links to the usage guide and privacy policy.… more - 🆕Proportion Calc: its developer released another app: 現場スキャン点群計測
- 🆕Proportion Calc released on the App Store
Collected from the stores by AppInsider since we first spotted the app. Dates are when we saw each change.
Rating
5.0 ★
1 ratings
Measured
Best rank now
#130
Business PaidMeasured
Proportion Calc on the App Store
App details
App ID
904107336
Publisher
youji okamura
On the store since
Aug 2014
12 years on the store
Minimum OS
iOS 16.0+
iPhone 8 and later
Devices
iPhone · iPad
Universal purchase
Content rating
4+
Languages
1
JA
Size
1 MB
Also listed in
Education
Where it ranks now
Every top chart it appears in across 30 countries.
| Country | Charts | Rank |
|---|---|---|
| Japan | BusinessPaid | #130 |
Apps near Proportion Calc on the chart
Business Paid, around #130.
Ratings
App Store, worldwide.
Rating
5.0 ★
1 ratings
Measured
Ratings
1
Measured
About Proportion Calc
Calculate corresponding side lengths using a₁ : b₁ = a₂ : b₂.
Diagrams, inputs, and results are shown together on one screen. Enter the reference height a₁ and horizontal distance b₁, then choose whether to calculate b₂ from a₂ or a₂ from b₂.
The right-triangle diagrams use blue for height a, teal for horizontal distance b, and orange for hypotenuse NL. The shapes update to match the entered proportions. Both the reference and calculated hypotenuse lengths are shown.
Copy results, save up to 20 calculations locally, and restore saved input conditions. Supports iPhone, iPad, Dark Mode, and accessible diagram descriptions. No account is required, and calculations and local history work offline.
The interface is in Japanese. Tap “例を入力” to try an example. Close the keyboard with “計算” to see the diagrams and results together.
Use the same unit for every length. The calculated side is rounded to three decimal places before NL is calculated. Verify results against project drawings and site conditions before construction work.
Official website and usage guide:
https://proportion-slope-calculator-jp.oka11.chatgpt.site/
Diagrams, inputs, and results are shown together on one screen. Enter the reference height a₁ and horizontal distance b₁, then choose whether to calculate b₂ from a₂ or a₂ from b₂.
The right-triangle diagrams use blue for height a, teal for horizontal distance b, and orange for hypotenuse NL. The shapes update to match the entered proportions. Both the reference and calculated hypotenuse lengths are shown.
Copy results, save up to 20 calculations locally, and restore saved input conditions. Supports iPhone, iPad, Dark Mode, and accessible diagram descriptions. No account is required, and calculations and local history work offline.
The interface is in Japanese. Tap “例を入力” to try an example. Close the keyboard with “計算” to see the diagrams and results together.
Use the same unit for every length. The calculated side is rounded to three decimal places before NL is calculated. Verify results against project drawings and site conditions before construction work.
Official website and usage guide:
https://proportion-slope-calculator-jp.oka11.chatgpt.site/
Latest updates
2.0
Redesigned the calculation screen to show diagrams, inputs, and results together.
Updated the forward and reverse calculation workflow and triangle diagrams. Added result copying, local calculation history, input validation, Dark Mode, and links to the usage guide and privacy policy.
