Sonnet
Checker.Fourteen lines, honestly judged

Three mechanical tests come first. Count the lines: fourteen. Count each line's syllables: ten, give or take a feminine ending. Mark the end rhymes as letters and see whether they land in one of the two canonical patterns — ABAB CDCD EFEF GG if you're writing in Shakespeare's shape, ABBAABBA plus a sestet if you're writing in Petrarch's.

Then comes the test that machines used to be useless at: does the poem turn? A sonnet is an argument, and somewhere — line 9 in the Italian tradition, the couplet in the English one — it has to pivot: question to answer, complaint to consolation, praise to doubt. The checker reads for that turn and tells you if it can't find one.

Paste your draft above and it runs all four tests at once, then goes line by line through weak spots with suggested fixes.

The Shakespearean sonnet builds in three quatrains, each with its own alternating rhymes, and settles the matter in a final couplet — a structure that rewards a snap of wit at the close. Its rhyme demands are gentle on English, which is poor in rhymes compared with Italian: seven different sounds, no sound used more than twice.

The Petrarchan sonnet divides into an octave and a sestet. The octave holds one idea inside just two rhyme sounds (ABBAABBA), which is why English Petrarchan sonnets are hard and why Milton and Wordsworth showing off with them still impresses. The sestet answers in a looser pattern — CDECDE and CDCDCD are both traditional.

If you only remember one distinction: Shakespearean sonnets resolve at the end, Petrarchan sonnets turn in the middle.

Two of the sonnet's requirements have dedicated deterministic instruments here, free and uncapped. The Iambic Pentameter Checker scans each line's stress pattern against da-DUM times five and flags the lines that don't scan. The Rhyme Scheme Finder letters your end rhymes phonetically, slant rhymes included.

A good workflow: draft, run the two mechanical checks until the skeleton is sound, then bring the poem here for the reading that judges whether the sonnet is any good — which is not a question syllable counts can answer.