
Herons Formula Calculator
Find triangle semiperimeter and area from all three side lengths.
Open toolCalculate all three triangle excircle radii. Provide Side a, Side b, Side c to compute results directly in your browser. Strict triangle inequality; r_a=area/(s-a) and corresponding denominators. Same length unit and stable Heron area. Inputs and results use floating-point numbers; output shows up to 12 significant digits. Rounding can occur.
Enter the inputs, then select Calculate.
Result will appear here
The Triangle Exradius Calculator evaluates Side a, Side b, Side c in client-side JavaScript using the deterministic rule below and updates the output panel immediately without uploading data to a server.
Calculate all three triangle excircle radii.
Strict triangle inequality; r_a=area/(s-a) and corresponding denominators. Same length unit and stable Heron area. Inputs and results use floating-point numbers; output shows up to 12 significant digits. Rounding can occur.
Review the input parameters, allowed value ranges, and worked reference cases for the Triangle Exradius Calculator below before running your calculation.
| Parameter / Scenario | Default / Sample Value | Rule or Allowed Range | Output / Usage Note |
|---|---|---|---|
| Input: Side a | 3 | Range: 1e-09 to 1000000000.0 | Required workspace parameter |
| Input: Side b | 4 | Range: 1e-09 to 1000000000.0 | Required workspace parameter |
| Input: Side c | 5 | Range: 1e-09 to 1000000000.0 | Required workspace parameter |
| Worked Case 1: Baseline run (Side a = 3) | Preloaded / test values | Calculate all three triangle excircle radii | Side a = 3; Side b = 4; Side c = 5. The displayed output is Exradius opposite a: 2 Exradius opposite b: 3 Exradius opposite c: 6. |
| Worked Case 2: Comparison scenario (equilateral triangle exradius formula) | Preloaded / test values | Calculate all three triangle excircle radii | Side a = 5; Side b = 5; Side c = 6. The displayed output is Exradius opposite a: 4 Exradius opposite b: 4 Exradius opposite c: 6. |
Follow these three steps to configure Side a, Side b, Side c, verify unit and boundary rules, and export your Triangle Exradius Calculator output.
Set side b, side c. Strict triangle inequality; r_a=area/(s-a) and corresponding denominators.
Select Calculate to see the three excircle radii. Copy result copies this text; Download saves it as a TXT file.
These concrete scenarios illustrate how the Triangle Exradius Calculator processes baseline inputs, comparison checks, and boundary constraints.
Side a = 3; Side b = 4; Side c = 5. The displayed output is Exradius opposite a: 2 Exradius opposite b: 3 Exradius opposite c: 6.

Side a = 5; Side b = 5; Side c = 6. The displayed output is Exradius opposite a: 4 Exradius opposite b: 4 Exradius opposite c: 6.

When solving for 'triangle exradius calculator', verify that Side a, Side b, Side c use consistent units and stay within the documented scope: Strict triangle inequality; r_a=area/(s-a) and corresponding denominators. Same length unit and stable Heron area. Inputs and results use floating-point numbers; output shows up to 12 significant digits. Rounding can occur.

The output panel reports the exact result derived from Side a, Side b, Side c alongside any unit or formatting notes.
The result is the three excircle radii. Find each external tangent-circle radius from triangle side lengths.
The radius labels identify the opposite side and require a nondegenerate triangle.
Numerical output shows up to 12 significant digits. Floating-point arithmetic and display rounding can affect the last digits.

Review these boundary constraints and validation rules before relying on the Triangle Exradius Calculator output.
Operational scope: Strict triangle inequality; r_a=area/(s-a) and corresponding denominators. Same length unit and stable Heron area. Inputs and results use floating-point numbers; output shows up to 12 significant digits. Rounding can occur. Inputs that violate minimum/maximum bounds or required format rules are rejected with a clear diagnostic prompt.
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Open toolAnswers about using Triangle Exradius Calculator and understanding its results.
The Triangle Exradius Calculator applies the rule: Calculate all three triangle excircle radii. Enter Side a, Side b, Side c into the workspace and the tool computes the exact output in your browser.
Yes. Provide Side a, Side b, Side c using the documented units and format shown in the quick reference table above. Preloaded default values let you test the workflow immediately.
Strict triangle inequality; r_a=area/(s-a) and corresponding denominators. Same length unit and stable Heron area. Inputs and results use floating-point numbers; output shows up to 12 significant digits. Rounding can occur. Confirm that your inputs fall within the allowed ranges before exporting the result.
Yes. All calculations for the Triangle Exradius Calculator execute 100% locally in your browser's JavaScript runtime. No inputs or results are uploaded to any external server.
Choose another tool for your next calculation, conversion, or text task.