# Reading Time Calculator

> Estimates how long a text takes to read silently from its word count and a reading speed, defaulting to 238 words per minute, the adult mean for non-fiction found in Brysbaert's 2019 meta-analysis; also gives the read-aloud time at 183 wpm.

- Calculator id: `reading-time` · Category: Everyday Life (`everyday`) · Tool name: `estimate_reading_time`
- Canonical page: https://tttkmbb.com/everyday/reading-time · This document: https://tttkmbb.com/everyday/reading-time.md · JSON definition: https://tttkmbb.com/everyday/reading-time.json

## Purpose

Estimates how long a text takes to read silently from its word count and a reading speed, defaulting to 238 words per minute, the adult mean for non-fiction found in Brysbaert's 2019 meta-analysis; also gives the read-aloud time at 183 wpm.

**Use when:** You need an estimated reading time for an article, book, speech or document, or want to convert a word count into minutes.

**Do not use when:** You need typing speed (use typing-speed) or the text is in a language or script with very different reading rates (adjust words_per_minute).

## Input

| Parameter | Type | Unit | Required | Description |
| --- | --- | --- | --- | --- |
| `word_count` | integer | words | required | Number of words in the text. (min 1, max 100000000) |
| `words_per_minute` | number | wpm | optional, default 238 | Silent reading speed. Adult means: 238 wpm non-fiction, 260 wpm fiction (Brysbaert 2019). (min 50, max 2000) |

## Output

| Field | Type | Unit | Description |
| --- | --- | --- | --- |
| `minutes` | number | min | word_count / words_per_minute. |
| `seconds` | integer | s | Same time in seconds (rounded). |
| `reading_time` | string |  | Formatted as hours, minutes and seconds. |
| `read_aloud_minutes` | number | min | word_count / 183 wpm, the adult mean for reading aloud in English. |

## Formula

`minutes = word_count / words_per_minute; read_aloud_minutes = word_count / 183`

Brysbaert (2019) pooled 190 studies: silent reading of English non-fiction averages 238 wpm (fiction 260 wpm); reading aloud averages 183 wpm. Skimming, dense technical text or a second language change the rate considerably.

## Data Sources

- Brysbaert M (2019) How many words do we read per minute? A review and meta-analysis of reading rate, J Mem Lang 109:104047 — https://doi.org/10.1016/j.jml.2019.104047 (peer_reviewed, retrieved 2026-09-23)

Data freshness: `static`. Deterministic formula with fixed constants; results never go stale. Inputs supplied by the caller determine the output.

## API

- `GET https://tttkmbb.com/api/v1/calculate/reading-time?word_count=…`
- `POST https://tttkmbb.com/api/v1/calculate/reading-time` with JSON body `{"inputs": {…}}`
- Response: unified envelope (`success`, `request`, `result.values`, `result.units`, `sources`, `freshness`, `timestamp`, `next_actions`, `links`); see https://tttkmbb.com/docs/response-format.md
- Schema: https://tttkmbb.com/api/v1/calculators/reading-time · OpenAPI operationId `estimate_reading_time` in https://tttkmbb.com/openapi.json
- Authentication: none. Rate limit: fair use, see https://tttkmbb.com/docs/rate-limits.md.

## MCP

- Server: `https://tttkmbb.com/mcp` (Streamable HTTP, JSON-RPC 2.0, no auth)
- Tool:  `run_calculator` with `{"calculator_id": "reading-time", "inputs": {…}}`

## Example

- 1500-word article at 238 wpm: inputs `{"word_count":1500}` → `{"minutes":6.3,"seconds":378,"reading_time":"6 min 18 s","read_aloud_minutes":8.2}`
- 80,000-word novel at 260 wpm: inputs `{"word_count":80000,"words_per_minute":260}` → `{"minutes":307.69,"seconds":18462,"reading_time":"5 h 7 min 42 s","read_aloud_minutes":437.16}`

```
GET https://tttkmbb.com/api/v1/calculate/reading-time?word_count=1500
```

## Limitations

You need typing speed (use typing-speed) or the text is in a language or script with very different reading rates (adjust words_per_minute). Brysbaert (2019) pooled 190 studies: silent reading of English non-fiction averages 238 wpm (fiction 260 wpm); reading aloud averages 183 wpm. Skimming, dense technical text or a second language change the rate considerably. All values are computed from the formula above; no measurement or live data is involved.

## FAQ

**Why 238 words per minute?**

It is the mean silent reading rate for adults reading English non-fiction across 190 studies (Brysbaert 2019); older '200–250 wpm' rules of thumb are consistent with it.

**How do I estimate speaking time for a speech?**

Use read_aloud_minutes (183 wpm) or set words_per_minute to 130–150 for a slow, deliberate presentation pace.

## Related

- [Typing Speed Calculator](https://tttkmbb.com/everyday/typing-speed.md) — Words per minute for typing rather than reading.
- [Time Duration Calculator](https://tttkmbb.com/everyday/time-duration.md) — Add the reading time to a schedule.