A poem in a real form

Three different things get checked, and they are not equally checkable. This app tries to be clear about which is which rather than presenting one confidence for all of them.

1. Counting is reliable. Lines, stanzas, and which lines repeat are simply counted. A villanelle either has nineteen lines or it does not. Syllables come from a word list of about twelve hundred entries plus rules over vowel groups, and the words English cannot agree on — fire, flower, hour, every, heaven — are never given a single number. Those lines are reported as a range rather than a single number, and a poem that hits its form on only one reading is labelled as such.
2. Rhyme needs pronunciation, not spelling. Love and move are not treated as a rhyme; cough, bough and though are three different sounds in one spelling. So rhyme here is decided from a curated table of rhyme families rather than from the last few letters. When a word is not in the table and its ending is one of the unreliable ones, this app says could not check — a third answer alongside rhymes and does not, reported as unverified rather than guessed at, and shown as its own badge.
3. Metre is stress, and stress is the hardest of the three. Iambic pentameter is not ten syllables; it is a pattern of alternating stress across them. A word of two or more syllables has its stress fixed by the dictionary, so it is evidence. A one-syllable word is not. English gives monosyllables their stress from the sentence, which is why the cat sat on the mat can be read as either an iambic line or a trochaic one. So monosyllables are excluded from the metre score entirely — not as agreeing, not as disagreeing, because the line assigns their stress and not the dictionary — and metre is reported as a fraction of the syllables whose stress English actually fixes, never as a bare yes.

What that means in practice. A line built entirely from short words — and English verse is full of them — will report that its length is right and its stress could not be checked. That is not the scanner failing; it is the scanner declining to score its own guess. A scanner that assigned the a weak beat and cat a strong one and then announced the line iambic would have proved nothing except that it wrote down the pattern it was looking for.

Measured, so you can weigh it: on the words in its own rhyme table, the spelling rules alone never contradict the curated pronunciation. On a held-out set of 62 pairs the table had never seen, it answered 38 and refused 24 — and of the 38 answers, none was wrong in either direction. The refusals are the price of that, and they are deliberate. The stress table is cross-checked against the syllable counter at load: any word where the two disagree is used by neither.

The scan is not a courtesy read-out; it is the check. Paste a poem you wrote and the free browser scanner returns its scheme, its syllable counts and its form findings with no account. Every poem the model writes goes through that same scanner, and the reconciliation compares what the model claimed against what was scanned: the claimed scheme against the scheme derived from the poem's own line endings rather than taken from the model's claim, the claimed metre against the measured fraction, and the claimed turn against where the turn actually falls. Every mismatch is shown. If it says sonnet and delivers thirteen lines, you are told.

Seven verse forms carry their real requirements, enforced rather than described: sonnet (fourteen lines and a turn), villanelle (nineteen lines with two refrains, tracked line by line), ballad stanza (quatrains alternating four and three beats), blank verse (unrhymed pentameter), free verse, ghazal (couplets with a repeated radif) and limerick (five lines, AABBA). Three of those checks are structural rather than metrical: villanelle refrain tracking, line by line; ghazal radif detection; and identity-rhyme detection — a word rhymed against itself is reported rather than counted as a rhyme.

Finished poems are saved to your SkillSafe account as a history, searchable by meaning rather than by exact words, and any poem can be copied or exported as Markdown, plain text or JSON.

The scanner is free, needs no model and no account, and always will be. Writing a poem is metered and needs an account. The line at the button shows what the run you have configured would reserve, in US dollars, before you commit to it — a reserve is a hold rather than a charge, and you are charged for what the run actually uses, which is usually far less.