Elena Marin
Founder · CEO
Lisbon, PT
Wrote those 800 cold emails. Then wrote the scorer.
About HighConvertingEmails
We're building the conversion layer email has been missing.
Most AI email tools chase volume and decoration. We chase the only metric that pays the bills — does the recipient actually act? That single bias drives every product decision below.
Founded
2025
Remote-first · headquartered in Lisbon
Bootstrapped, profitable
Our story
It started with one cold email no one opened.
In late 2024 our founder shipped 800 cold emails to introduce a new SaaS. Reply rate: 0.4%. Open rate looked “fine” — but the actual outcome was the only signal that mattered, and that signal said the copy was the bottleneck, not the list.
Existing AI tools all said the same thing: “Make it friendlier!” They were optimizing for vibes, not for the ask. So we built a private scorer that graded emails against a real conversion rubric: clarity, CTA strength, persuasion structure, spam triggers, AI-tells, brand-voice consistency.
Two weeks of iteration later, that same list converted at 4.8%. We open-sourced the rubric, then realized other operators needed it too. HighConvertingEmails became the product version of that internal tool.
12
Sharp tools, one workspace
<2s
Average time-to-first-variant
~88%
Prompt-cache hit rate (and rising)
11
AI prompts, version-tracked + eval-tested
100+
Hand-curated templates ready to remix
0
Investors required to ship — we're bootstrapped
What we believe
Four principles, no committee-speak.
Conversion over decoration.
We obsess over the metric that ends in money. Aesthetics matter, but only when they serve the ask.
Honesty compounds.
We tell users when our prediction is just a calibrated guess. We tell competitors when they're better.
Narrow and deep.
Email is a discipline. We'd rather be the best at one thing than mediocre at five.
Ship the unglamorous.
Spam-lint, deliverability checks, and prompt caching aren't demo material. They're half the reason it works.
“The best email tool is the one that makes the email harder to write, not easier. Easy email is the enemy of good email. We'd rather watch you wrestle a sentence than ship a polished one no one opens.”
Our founding memo
Milestones
From napkin scribble to bootstrapped product.
- Nov 2024Nov 20240.4% reply rate, one founder.First version of the scoring rubric, written on a napkin.
- Jan 2025Jan 2025Private AI scorer.Internal tool ranks 1,200 historical emails and surfaces the same five mistakes everyone makes.
- Mar 2025Mar 2025Public alpha.200 operators get rewrite + score. Median lift: +18 points on the rubric, +2.4× reply rate.
- Jun 2025Jun 2025Beta with sequences + brand voice.Drip coherence and 5-sample voice extraction land. First paying customers.
- Sep 2025Sep 2025Public launch.Pricing, public API, Chrome extension, free tools, 100+ template library.
- TodayTodayBootstrapped, profitable, opinionated.Still narrow. Still deep. Still not building a chat wrapper.
The team
Eight humans, spread across four continents, one timezone.
We standardize on UTC and async writing. The reason your reply time feels short is that someone, somewhere, is awake.
Marcus Tate
Co-founder · Head of Product
Brooklyn, NY
Built CRM tooling for 8 years. Knows where reps actually waste their time.
Priya Raghavan
Engineering Lead
Bengaluru, IN
Built our streaming infra and prompt-cache strategy. Cares about p99.
Diego Costa
Design
São Paulo, BR
Quietly responsible for every pill button you've clicked.
Anna Vogel
Growth
Berlin, DE
Runs every send through our own scorer. Above 80 or it doesn't ship.
Kenji Park
AI Research
Seoul, KR
Versions our prompts the way other people version code. Eval-driven.
Sofia Reyes
Customer Success
Mexico City, MX
Answers within an hour because that's when you actually care.
Noah Bennett
Operations
Edinburgh, UK
Keeps the lights on and the contracts sane. Former finance, former skeptic.
Culture
Remote, async, calm.
Async by default. Two meetings a week, both optional. Decisions live in writing — usually in a thread anyone can find six months later.
Distributed by design. Four continents. Twice a year we meet in person; the rest of the year we trust the writing.
Boring on purpose. Health insurance, proper PTO, salary bands published internally. No ping-pong table, no “family.”
Opinionated, kindly. Disagree in writing, decide quickly, commit fully. Then ship.
In the press
People we respect have written about us.
The Verge
TechCrunch
Hacker News
Indie Hackers
Lenny's Newsletter
Press contact: press@highconvertingemails.com
Backed by
Operators & angels, not growth capital.
We took a small angel round in mid-2025 from people who've actually run email programs. The cap table looks like a customer advisory board.
Northwind Ventures
Pre-launch placeholder name
Opalsend Capital
Pre-launch placeholder name
Pierside
Pre-launch placeholder name
Loop.io Angels
Pre-launch placeholder name
Working with us
Open roles.
We hire slowly. Salary bands are published in the role. Take-home exercises are paid and time-boxed. No whiteboard riddles.
Don't see your role? Write to us anyway.
Score, then rewrite. Catch the lazy patterns in a cold email and see why a line is weak — not just what to swap it for.
Product principle · HighConvertingEmails
Say hi
Real humans, <1 hr reply time.
The address that gets a reply is hello@highconvertingemails.com. Press, partnerships, weird ideas — all welcome.
- Median reply time under an hour, in business hours somewhere on earth
- We answer technical questions ourselves — no support tier escalation
- If you found a bug, we'll fix it before the reply lands