Your book already has a logline — you named it in four parts
A logline is not a summary. It is not the back cover. It is not the tagline the poster will carry in seven words. A logline is one sentence that names four parts so a buyer can picture who wants what, who is in the way, and what is lost if they fail. Protagonist, want, obstacle, stakes. The four are the promise. The book already has them; the tool just makes them visible as one sentence that scans.
A disgraced detective must find a missing girl before the snow seals the town, but a sheriff who buried the last case stands in the way — and failure means the town loses its last chance at justice. That sentence is the same four parts the cover brief will later use. It also reads aloud cleanly at about 27 words and about 150 characters, inside the 80 to 180 window that fits a one-line pitch. The sentence carries the cast (detective), the verb (find), the blocker (sheriff), and the cost (justice). The buyer hears who, what, who stops them, and the price.
The same four-part shape works when the nouns change. A banished chef wants to claim the ember spice that restores taste, but the warlord who sealed the valley forces a choice where the last kitchen falls. A smuggler will deliver the cure or watch the colony die — unless a blockade stops them first. Thriller wants find, fantasy wants claim, science fiction wants deliver, romance wants choose. The verb carries tone, the four parts carry structure.
The four parts, and how short to keep them
The protagonist should be two to five words that cast. A disgraced detective reads as a type the room can picture and name an actor for. A young woman is not castable until the adjective does work — a young coder who sold her first company is. Keep the protagonist to the phrase that implies casting, not a biography. The tool counts protagonist words so you can see when the phrase that should be two to five runs to eight.
The want should be a verb plus an object. Find a missing girl before the snow seals the town is a verb and an object with a clock. Claim the ember spice that restores taste is a verb and an object with a promise. Ship her app is a verb and an object but has no clock; find a missing girl before the snow seals the town does. The want should be one goal, not two, and the tool counts want words so you can see when a single goal has sprawled to two.
The obstacle should be a person or a system that actively blocks the want. A sheriff who buried the last case is a person who will choose to block. A powerful conspiracy is a system that will. Difficulty is not an obstacle — trust issues, self-doubt, time — until the difficulty has a face. The obstacle should be active: it stands in the way, it forces a choice, it sealed the valley. The tool treats an empty obstacle as a missing part and warns — a logline with three parts reads as a premise with a missing promise.
The stakes should be specific and outside the protagonist. The town loses its last chance at justice is outside the detective and costs the town. She loses funding is outside the coder but narrow; the last kitchen falls is outside the chef and costs a culture. Stakes that are only inside the protagonist — she loses confidence — rarely sell the film until they are made outside — she loses the last kitchen that taught her. Keep stakes to what is lost if they fail, where failure is a concrete loss the audience can weigh.
Three variants from the same four parts
The same four parts produce at least three one-sentence variants that pitch differently. The tool builds all three and reports the characters and words so you can keep the one that lands on stakes, not setup.
The classic When structure is 'When protagonist must want, obstacle stands in the way — and failure means stakes.' It is the tightest way to name all four without a second clause. When a disgraced detective must find a missing girl before the snow seals the town, a sheriff who buried the last case stands in the way — and failure means the town loses its last chance at justice. About 150 characters, about 27 words, classic thriller rhythm.
The character Wants But structure is 'Protagonist wants want, but obstacle forces a choice where stakes hang in the balance.' It foregrounds desire. A disgraced detective wants to find a missing girl before the snow seals the town, but a sheriff who buried the last case forces a choice where justice hangs in the balance. Slightly longer, more interior, better when the protagonist's agency is the sale.
The hook Will Unless structure is 'Protagonist will want or watch stakes — unless obstacle stops them first.' It foregrounds clock. A disgraced detective will find a missing girl or watch the town lose its last chance at justice — unless a sheriff who buried the last case stops them first. shortest, most trailer-friendly, best for the poster line.
The three variants are three views of the same four parts. The classic carries the inciting incident as When; the character carries the protagonist's agency as Wants; the hook carries the clock as Will Or Watch. The room expects one, not three; the tool shows three so you can keep the one that reads aloud cleanly and maps to the tone you pitched.
How long the pitch should scan
A logline should scan in one breath at about 22 to 28 words. Shorter reads as a premise without stakes; longer will not fit the one-line that development and the key art brief expect. The tool counts characters for the poster constraint — fits one line at 80 to 180 — and words for the breath — about 25 — so both constraints stay visible.
At the classic 27 words and 150 characters, the thriller example is inside both windows. At 34 words when the want sprawls to find a missing girl before the snow seals the town and the roads close and everyone forgets she existed because the last search was buried, the classic becomes 220 characters and the verdict is warning — long where it should be tight. The fix is to cut the want clause to a verb and an object again, not to keep the extra geography as proof of thoroughness. The extra geography belongs in the synopsis, not the logline. The logline that survives is the one that ends on stakes, not setup.
The hook at 22 words and 120 characters is the shortest of the three. The character at 29 words and 160 characters is the longest. The three together bracket the ideal one-line window. The single line to quote is the one that fits where the line must fit — development's database, the key art brief's headline field, the catalogue's one-liner.
Tone carries through verbs, not adjectives
Thriller, drama, comedy, fantasy, science fiction, horror, romance, and adventure use the same four parts; only tone and verb change. Thriller wants find and stop, fantasy wants claim and defend, science fiction wants deliver and survive, romance wants choose and risk, horror wants escape and survive, comedy wants pretend and become, drama wants reconcile and forgive. The verb should be consistent with the tone you pitched so the same logline does not read as two films.
The tool takes tone as the last input so the four parts do not change when tone does, and the logline remains the same sentence viewed through a different genre's verbs. The adaptation scope that keeps four parts does not shift when tone is changed to comedy; the same disgraced detective's story can be a thriller at find or a comedy at pretend, but the want remains find, and the verb that shifts is the performance.
Castability check — does the protagonist imply casting
A logline that keeps protagonist, want, obstacle, and stakes but makes the protagonist vague will not cast. A young coder wants to ship her app but a blockade forces a choice where funding hangs reads as stakes outside but the protagonist at two words young coder does not imply a type the room can picture. A disgraced detective at two words plus one adjective does. The tool reports the protagonist word count so you can see when the castable phrase at two to five runs to eight because the protagonist is a biography rather than a type.
The fix for a vague protagonist is not more adjectives. It is a specific history that implies casting: a chef who lost taste, a smuggler with a debt, a teacher who buried a trial. The specific history carries the role's wound, and the wound carries the casting.
Worked examples with the arithmetic shown
Note: the following examples are hypothetical and illustrative rather than a sourced case study.
A disgraced detective thriller. Protagonist a disgraced detective at three words, want find a missing girl before the snow seals the town at nine, obstacle a sheriff who buried the last case at seven, stakes the town loses its last chance at justice at nine, tone thriller. The classic When structure is 149 characters at 27 words; the character Wants But is 162 characters at 28; the hook Will Or Watch is 133 characters at 23. All three are inside 80 to 180 and inside 22 to 28. The metrics show three variants with those counts, the breakdown shows the three trimmed to 70 characters each with a note of chars — when protagonist must want, the recommendation says read the three aloud and keep the one that lands on stakes. The verdict is pass — three loglines ready to pitch.
A banished chef fantasy with the same four-part shape. Protagonist a banished chef at three, want claim the ember spice that restores taste at seven, obstacle the warlord who sealed the valley at six, stakes the last kitchen falls at five, tone fantasy. The classic becomes When a banished chef must claim the ember spice, a warlord who sealed the valley stands in the way, failure means the last kitchen falls at about 140 characters at 25 words. The structure is the same as thriller; only the nouns changed. The verdict is pass. The recommendations say the fantasy wants claim and defend at this tone, and the protagonist at three words implies casting as a chef with a past.
A missing obstacle. Protagonist a young coder at three, want ship her app at three, obstacle empty, stakes she loses funding at three, tone drama. Four parts become three, 3 of 4 filled. The classic becomes When a young coder must ship her app, stands in the way — malformed because the obstacle clause is empty and the em dash leads to a gap. The tool generates the best it can with an empty part but the verdict is warning — add the missing parts — logline needs all four, at 1 of 4 parts filled. The metrics show three variants still built but short; the breakdown shows obstacle trimmed to dash. The recommendation says fill the obstacle with a person or system that actively blocks.
Why the tool stops at the logline, not the synopsis
The logline shows four parts in one sentence. The synopsis shows those four parts expanded to a paragraph that names act turns — inciting incident near 10 percent, first plot point near 25, midpoint near 50, crisis near 75, climax near 90 — and the proposal shows them expanded to a deck. Each expansion keeps the same four parts. The logline that names them as When, Wants, and Will Or Watch is the promise that the synopsis and deck then keep.
Common mistakes and how to avoid them
Naming the book title in the logline is the first. The logline is about the story, not the title. The title sells recognition; the logline sells the adaptation. Keep them separate for the buyer. Using the title Inside the Logline inserts the name of the product where the promise should be.
Pitching a premise with three parts is the second. A premise with protagonist, want, and obstacle but no stakes reads as Will She Do It without What She Loses. Stakes make the promise matter outside the protagonist.
Writing a logline longer than 180 characters is the third. At 220 characters the question When a Disgraced Detective Must Find a Missing Girl Before the Snow Seals the Town and the Roads Close and Everyone Forgets She Existed Because the Last Search Was Buried reads as a map, not a pitch. The long logline belongs in the synopsis.
Choosing tone to shorten the estimate is the fourth. A thriller at find does not make the same fantasy shorter; it makes a thriller with the same word count that happens to be called fantasy. Tone is the verb, not the setting.
Carrying the keep ratio as a variable the room can dial is the fifth. A keep of 15 instead of 12 for a short is not a longer logline but a loose cut.
Quoting total for a multi-part without per-part is trap six when the target chain widens.
Final checks before you commit
Run the tool twice with two tones that bookend your manuscript — for example, thriller and drama for a thriller that has lyrical passages. The estimate should bracket the true logline within a small window; the genre that should be pitched is the genre whose verbs the screenplay actually uses.
Read the three variants aloud. The logline should scan in one breath and end on stakes, not setup. The logline that lands on stakes is the one the room repeats.
Compare the logline to the cover. A short film cover that sells a short tier should not promise the full book; a multi-part cover that sells an uncut total should not hide the per-part.
Run the tool once with the true protagonist and want and once with the protagonist plus title — typically the protagonist already carries the title's promise. The true protagonist is the one whose minutes matter and whose casting the room can name.
Engineering note — the table is the map
The table that shows protagonist, want, obstacle, stakes as Parts You Entered → What the Audience Hears is the map of the cut the outline must budget. It is not a menu.
Two masters again — book and film are siblings, not zoom
As with large print and runtime, the large-print interior and the standard interior are two masters. The book's logline and the film's logline are siblings, not zoom. The book's 273 pages, its 88 thriller scenes, and its 90 minutes of screened time plus its one-sentence logline are siblings derived from the same source manuscript by different operations.
Book to Film triad — minutes, scenes, scope, logline
Book to Film needs four numbers before any blade touches outline: minutes, scenes, scope, and logline. Minutes tells the buyer the clock; scenes tells the writers room the units; scope tells whose scenes stay; logline tells the room what to say in one sentence. Minutes from the runtime estimator, scenes from the scene counter, scope from the planner, and logline from this generator are the four. The logline is the sentence that sells the minutes.
Checklist before you pitch the logline
First, name the protagonist. Second, name the want. Third, name the obstacle. Fourth, name the stakes. Fifth, pick the variant that reads aloud cleanly. Sixth, compare the logline to the key art brief the film will need. Seventh, run the tool again with the opposite tone to bracket the true logline.
Why this page sits where it does
Logline sits after scope because scope names the keep and logline names the promise that survives the keep. Without scope the logline is a promise without a cut to keep it. With scope the logline is the promise the kept chapters must keep.
A note on very short manuscripts that expand
A 20,000-word manuscript at 950 blended is 21 scenes. The logline at four parts can still be built — a short story's logline is the same four parts as a novel's. The logline at that thin end is not keep, compress, and cut but invent — the writer must invent beats the book did not have. The logline is the four parts even for a short.
Engineering depth — the divisor chain
Words per page is 275 at 6×9 Garamond 12 on 15.5, words per scene is 850 thriller and 1,250 fantasy at the same trim, screened words per minute is 135 spoken. The three divisors chain: words divided by 275 is pages, words divided by 950 blended is scenes, words times 0.12 divided by 135 is minutes before genre pace. The four divisors input is the same word count. The outputs are the four masters plus the logline: pages, scenes, minutes, scope, promise. The chain's input is the same word count. The outputs are the masters plus the promise the logline carries.
The cost of a logline merged vs a subplot cut
Every logline merged in adaptation has a location cost. Merging two thriller loglines that share a location saves a company move but costs a beat where character could have turned. The 19 cut and the 28 compress for the 75k thriller to 90 are locations not moved to, beats not turned at, and subplots not carried. The logline's stakes — the town loses its last chance at justice — keeps the cost visible as a sentence, not hidden as a single logline number.
Final pass — verify twice
Run the tool twice with two protagonists that bookend your manuscript — for example, thriller and drama for a thriller that has lyrical passages. The estimate should bracket the true logline within a small window; the genre that should be pitched is the genre whose verbs the screenplay actually uses.
A final worked pass
A debut at 82,000 words in Word.