Backstroke Sandbox • Paste Your Body

Paste Your Body

Paste your body and we'll return subject line copy so good it'll make the hair on the back of your neck stand up 👅

1Show us your body

Paste the body copy of your next promotional email into the form below

2Sit tight for 24 hours

Give us about one day to review your body and prepare for the big moment

3Choose your favorite

Review three AI-generated subject lines, pick your favorite, and copy/paste it into your campaign.

Give us that body. Maybe we should buy you dinner first.

Backstroke is powered by insights and performance data from 10,000+ B2C brands. Auto-magically create email, SMS, and push campaigns that perform at least 31% better.

Dive headfirst into more revenue

More Tools in the Sandbox:

Free AI Email Tools from Backstroke

Use our free AI tools to write, analyze, and optimize your way to email, text, and push heroics. See what other toys we have in the box — just try to keep the sand out of your pants.

Subject Line Generator

Plug in your campaign type and kick your sandals off while SLG writes predicted-to-perform copy before eyes.

Trends Lite

What emoji was trending last week? Which subject lines were overused in your industry? Find this and more in a free version of our enterprise trends product.

Paste Your Body

Drop in your body copy and let Paste Your Body draft the perfect subject line and preheader combo. Don't let the name fool you, this free tool is no joke.

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