# runtime

Source: https://englishreference.com/word/runtime
Updated: 2026-08-27

## Senses

### 1. computing execution time

noun · CEFR B2 · Technical

the time when a computer program is actually working or running.

For teachers: the period during which a computer program is executing, as opposed to other phases of the software lifecycle like compile time.

- The app crashed at runtime because it couldn't find the database.
- The developers spent weeks optimizing the code to reduce runtime errors and improve the overall efficiency of the server-side processing.

Usage: Often used as a compound noun or as an adjective modifying 'error' or 'environment'.

### 2. duration of a film

noun · CEFR B2

the total length of time a movie, play, or piece of music lasts.

For teachers: the total duration of a film, theatrical performance, or recorded media from start to finish.

- The movie has a runtime of three hours, so we should buy snacks.
- Despite its lengthy runtime, the documentary maintains a brisk pace that keeps the audience engaged through every historical reenactment.

## Examples

- The movie has a runtime of two hours.
- The software developer optimized the code to reduce the application's runtime and improve the user experience.
- While the director's cut features a three-hour runtime, the theatrical version was edited down to two hours to ensure more frequent daily screenings at local cinemas.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.