For brand & growth teams
Find the newsletters your buyers actually read
Most sponsorship plans are built from the same handful of names. NewsletterFIT lets you search the whole market by topic, see who each newsletter is written for and how actively it publishes, and check which brands already buy placements there.
7 days of Pro, no credit card required
The problem
The obvious newsletters are the expensive ones
Rates follow attention. By the time a newsletter is on every list, its slots are booked and its price has moved. The newsletters that fit your audience best are often mid-sized, niche and still growing, and they rarely show up in a Google search or a media kit pile.
What you can do
Build a shortlist from the whole market
Search by topic, company or keyword and rank by audience, posting cadence and momentum. Save the ones that fit to a watchlist.
Newsletter searchSee who already sponsors a newsletter
Every newsletter profile shows the brands detected in recent issues, so you know whether your category already buys there and how often.
Sponsor intelligenceCatch newsletters while they are still growing
Rising lists surface newsletters with sustained subscriber growth, so you can open the conversation before the rate card changes.
Rising newslettersTrack your competitors' placements
Add a competitor to your alerts and get an email when they appear in a newsletter you track, sponsored or not.
Alerts
Example
A live slice of one topic
Real newsletters from the index for one topic, with audience and publishing activity. Sponsor names unlock in the app.
beehiiv · Several times a week · Cybersecurity · AI safety
Likely audience · ML engineers
Sponsors · None detected recently
Activity · 39 posts in the last 90 days · last post 8 days ago
beehiiv · Several times a week · AI agents · Investment strategy
Likely audience · Investors
Sponsors · None detected recently
Activity · 50 posts in the last 90 days · last post 7 days ago
substack · Several times a week · AI infrastructure · AI application pricing
Likely audience · Venture capitalists
Sponsors · None detected recently
Activity · 50 posts in the last 90 days · last post 8 days ago
beehiiv · Several times a week · AI regulation · AI security
Likely audience · AI researchers and engineers
Sponsors · None detected recently
Activity · 34 posts in the last 90 days · last post today
How it works
01
Search your category
Start from a topic your buyers care about, or a competitor's name.
02
Narrow to fit
Filter by audience size, cadence, platform and sponsor activity.
03
Save and monitor
Put the shortlist on a watchlist and get alerted when something changes.
FAQ
Which newsletters does NewsletterFIT cover?
Public newsletters on Substack, beehiiv and custom domains. We read public archives, RSS feeds and sitemaps, so anything a reader can see without logging in can be indexed.
Do you have open rates or private publisher metrics?
No. Subscriber figures are what the platform shows publicly. We add what we can observe from the content itself: who it is written for, how often it publishes, which topics it covers and which brands it mentions or carries as sponsors.
Can I book a placement through NewsletterFIT?
Not yet. NewsletterFIT is the research step: it tells you where to spend and what the newsletter already carries. You contact the publisher directly.
How current is the sponsor data?
Newsletters are re-read on a rolling schedule and sponsor placements are detected from each new issue. The methodology page explains how detection works and how fresh each newsletter is.