Gunning Fog Index

Text nobody finishes usually has two habits: sentences that run forever and words with too many syllables. Gunning Fog folds both into a single number that estimates the years of schooling a reader needs to follow along. Paste your text and the index updates live. The sample sentence preloaded in the box scores 38.2, well off any sensible scale, because seven of its eight words carry three or more syllables.

A complex word here is any word with three or more vowel groups. Robert Gunning's original definition carves out exemptions this version does not apply: proper nouns, jargon the audience already knows, compound words, and verbs that only reach three syllables because of an ending such as -ed or -es. Without those carve-outs the number runs higher than the classic Fog would give you, especially in text dense with names.

Read the score comparatively. Measure, split the long sentences in two, swap three inflated words for plain ones, then measure again; sentence length is the cheapest lever you have. Check that your sentences actually end in punctuation, because without it the whole passage counts as one sentence and the index explodes. As a rough map, 8 to 12 suits a general audience and anything past 17 reads like a contract. It all runs in your browser.