What does the cognitive load score represent?

The cognitive load score is a simple 0–100 style indicator of how demanding a text may feel to a general reader. It combines average sentence length, the proportion of long sentences, the proportion of long words and an estimate of how much technical content or acronyms appear. It is a rough heuristic, not a clinical or psychological measure.

Who might find this reading time and load estimator useful?

Writers, editors, teachers, UX and content designers, documentation authors and anyone planning learning materials can use this tool to check approximate reading time and effort for a page, article, email or lesson handout before sending it to readers.

How accurate is the reading time?

The reading times are based on typical words-per-minute benchmarks for skim, normal and careful reading. Real readers vary, and context also matters, so you should treat the times as a ballpark guide rather than a precise stopwatch value.

Does this tool store or upload the text I paste?

No. All analysis runs locally in your browser using vanilla JavaScript. The app does not upload, store or log the text you paste, and refreshing the page clears everything.

Reading Time + Cognitive Load Estimator

Paste any article, report, email or lesson handout to get a quick estimate of reading time and a rough cognitive load score based on sentence length, long words and “technical” density.

Who is this for? Writers, editors, teachers, UX and content designers, documentation authors and anyone who wants a reality check on how demanding a piece of text might feel before sending it to real people.

Step 1

Paste your text

Text to analyse

The estimator uses word count, sentence boundaries and simple word patterns. It does not understand meaning; think of it as a mechanical complexity checker.

Audience context (optional)

Intended audience

This doesn’t change the raw metrics, but nudges the guidance text — for experts, higher load is often acceptable.

Step 2

Reading time & effort

Total words –

Characters (no spaces) –

Sentences –

Paragraphs –

Estimated reading time

Based on typical words-per-minute benchmarks: skim ≈ 275 wpm, normal ≈ 200 wpm, careful ≈ 125 wpm.

Skim read –

Normal read –

Careful read –

Cognitive load (approximate)

–

Average sentence length: –
Long sentences (> 25 words): –
Long words (≥ 13 characters): –
Technical / numeric density: –
Vocabulary variety (type–token ratio): –

Reading time & load estimator FAQ

How the estimates are calculated, what the cognitive load score means, and how to use it in practice.

How is reading time calculated?
Reading time is simply word count ÷ words per minute for three speeds:
- Skim ≈ 275 wpm — scanning for gist.
- Normal ≈ 200 wpm — engaged but not intense.
- Careful ≈ 125 wpm — close reading, study or note-taking.
Real readers vary, so treat these as ballpark values to compare drafts or sections rather than exact timing.
What goes into the cognitive load score?
The score combines several mechanical features of the text:
- Average sentence length.
- Percentage of very long sentences (> 25 words).
- Percentage of long words (13+ characters).
- Estimated “technical density” — words with digits or multiple capitals (IDs, acronyms, codes).
- Vocabulary variety (unique words vs total words).
Longer sentences, more long words and a lot of IDs/acronyms all push the score up.
How should I use the score when editing?
Rather than chasing a perfect number, use the metrics to guide edits:
- If average sentence length is high and long-sentence percentage is large, consider splitting sentences.
- If technical density is high for a general audience, clarify or reduce acronyms and codes.
- If vocabulary variety is very high, check for synonyms that could be simplified.
For expert audiences, a higher score is acceptable; for the general public or early learners, aim for lighter to moderate load where possible.
Is this a formal readability or psychological measure?

No. This is a simple, transparent heuristic. It does not implement formal clinical or psychological models of cognitive load, and it is not a substitute for user testing or accessibility reviews. It is best used as a quick sense-check when drafting and editing.

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