Convertools

Arccosine to Radians

Calculate inverse cosine and return the principal angle in radians.

Author

Prof. Priya Venkatesh

Math editorial contributor

Indian theoretical physicist from IIT Bombay with postdoctoral work at CERN, researching dark matter candidates

Reviewed by

Dr. Emeka Nwosu

Math content reviewer

Nigerian legal scholar with an SJD from Yale, focused on international trade law and African continental free trade agreements

Last updatedFebruary 22, 2026

PublishedFebruary 22, 2026

Table of Contents

  1. Reference values
  2. Calculator
  3. Reference table
  4. FAQs
  5. Methodology and review
  6. Related conversions

0 Cosine Value =

1.570796 rad

Representative value from the Arccosine to Radians reference table.

Reference Values

Browse 15 reference values with individual detail pages for quick lookup.

Browse all reference values

Arccosine to Radians

Calculate inverse cosine and return the principal angle in radians.

Calculated Result

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Reference Table

Use this complete table for quick lookup and internal linking to specific value pages.

Arccosine to Radians Reference
Cosine Valueacos(x)
-1 Cosine Value3.141593 rad
-0.95 Cosine Value2.824032 rad
-0.9 Cosine Value2.690566 rad
-0.8 Cosine Value2.498092 rad
-0.75 Cosine Value2.418858 rad
-0.5 Cosine Value2.094395 rad
-0.25 Cosine Value1.823477 rad
0 Cosine Value1.570796 rad
0.25 Cosine Value1.318116 rad
0.5 Cosine Value1.047198 rad
0.75 Cosine Value0.722734 rad
0.8 Cosine Value0.643501 rad
0.9 Cosine Value0.451027 rad
0.95 Cosine Value0.31756 rad
1 Cosine Value0 rad

Frequently Asked Questions

Common questions about Arccosine to Radians, formulas, and typical use cases.

What does the Arccosine to Radians calculator do?

It helps with recovering angles from known cosine values in trig and vector calculations.

What formula does the Arccosine to Radians calculator use?

acos(x) returns the principal inverse cosine angle in radians, in the range [0, π].

What inputs are valid?

Input must be between -1 and 1 inclusive for real-number results.

When would I use this?

recovering angles from known cosine values in trig and vector calculations

Methodology and Review

This page combines a live calculator, precomputed reference values, and FAQ content from the same conversion definition to reduce mismatch between calculator output and lookup tables.

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For compliance-sensitive work, verify final values against project requirements, governing standards, and manufacturer documentation.