Ontfly — Find out if it sells before you build it

Sign inTest my ideaFind out if it sells<br>before you build it.<br>Describe your idea. Ontfly puts a real page and real ads in front of real people, and tells you what it cost to get a signup.<br>Calorie tracking appHabit trackerMeditation app

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Free preview · no card<br>I already have a websiteAlready running a business? Connect itTest it for free · go live from $39/mo

ontfly/ Plateful<br>Day 9 of test<br>plateful.ontfly.ai

ResultsAdsSiteSocialBuild<br>Visitors<br>2,140<br>from ads

Signups<br>168<br>$1.07 each

Paying<br>43<br>25% of signups

Revenue<br>$1,247<br>on $180 spend

Revenue · cumulative6.9× on ad spend<br>Day 1Day 9

Ad creatives · 3 variantsExample<br>Sponsored0:14I stoppedGUESSINGmy calories

I stopped guessing<br>8.1×· best

Sponsored0:11POV: your fridgeTELLS YOUwhat to eat

Fridge POV<br>5.2×

Sponsored0:09Whole day loggedIN 3 TAPS

Three taps<br>1.4×

Written, cut and captioned from the same one-paragraph brief — then run against each other so the winner is decided by cost per signup, not by taste.

Ads Manager · last 9 daysExample<br>Ad setSpendSignupsCost / signupROAS<br>UGC · "I stopped guessing"$92104$0.888.1×<br>UGC · "Fridge POV"$6151$1.205.2×<br>UGC · "Three taps"$2713$2.081.4×

Paused on its own — cost per signup ran 2.4× the others.

An example test — a calorie tracking app, nine days, $180 of ads. Sample figures, not a typical result.<br>Test my ideaYours takes one paragraph to start.Free · no card

01How it works<br>An idea on Monday. A verdict by Friday.

A calorie tracker that logs a whole meal from one photo.

Got it. Who do we test it on first — dieters, gym regulars, both?

DietersGym regularsBoth

Step 01<br>Describe the idea<br>One paragraph — what it is and who it's for. No spec, no deck, no designer. It asks back if anything's missing.

Ad creatives · 3 variants<br>0:14I stoppedGUESSINGmy calories

I stopped guessing<br>8.1×

0:11POV: your fridgeTELLS YOUwhat to eat

Fridge POV<br>5.2×

0:09Whole day loggedIN 3 TAPS

Three taps<br>1.4×

Step 02<br>The page and the ads go live<br>A real landing page on a real URL, ad creatives written and cut, a small daily budget ready to run. You approve in two clicks.

Ads Manager · last 9 days<br>Ad setSignupsCost<br>UGC · "I stopped guessing"104$0.88<br>UGC · "Fridge POV"51$1.20<br>UGC · "Three taps"13$2.08

Paused on its own — cost per signup ran 2.4× the others.

Step 03<br>You get an answer, not a hunch<br>Clicks, signups, cost per signup, revenue. Kill it, change the angle and retest, or tell it to build the real product.

Test my ideaOne paragraph is the whole setup. It asks you the rest.Free · no card

02What goes live<br>A real page.<br>Real ads.<br>Real signups.<br>A survey tells you what people say. A live page with money behind it tells you what they do. Everything below ships on day one — no designer, no ads agency, no dashboards to stitch together.<br>01A landing page<br>On a real URL people can actually visit — not a mockup or a Figma frame

02The ads<br>Meta creatives written, cut and launched on a daily budget you set

03Signups & payments<br>Emails captured, Stripe checkout wired the moment you want to charge

04The numbers<br>Visitors, signups, cost per signup, revenue — one screen, no spreadsheet

Test my ideaAll of it live on day one.Free · no card

plateful.ontfly.ai

A real page Ontfly generated from one paragraph — copy, layout and imagery. Nothing on it was designed by hand.

04Day one<br>What the first day actually looks like.

Example test · PlatefulDay 1 of 9<br>09:02siteLanding page live at plateful.ontfly.ai — signup form wired<br>09:31adsThree UGC variants cut · 9–14s, captions burned in<br>10:12adsMeta campaign live · $20/day · US, 25–44, fitness interest<br>11:14signupFirst signup — 41 minutes after the ads went live<br>12:08adsPaused “Three taps” — cost per signup ran 2.4× the others<br>13:40metrics312 visitors · 24 signups · $0.91 each<br>17:30verdictEnough signal to keep spending — plan for day 2 readydone

Test my ideaDay one starts the moment you describe it.Free · no card

Test it first.<br>It's free.<br>Draft the page, the ads and the creatives for free. From thirty-nine dollars a month when you're ready to put spend behind it.

Test my ideaFrom $39/mo to go live · cancel any time