GTM AI Index

Index › Products › Postmark · October 2026 Edition

ActiveCampaign · 1 category · Named, not ranked

Postmark

20Judge labels

1First choices

1Negative labels

10 / 14Models named it

1Category

October 2026 Edition. Every number here is derived from the raw labels under vendor table v2026-10-05.2, every buyer segment counted.

Standing

4 labels, too few to rank

A product needs 10 labels in a category before a share or quadrant is stated. Postmark was named 4 times in Email deliverability, where GlockApps led with 34%. The labels and the evidence are below, counted exactly.

By buyer segmentRead the same way at every buyer size.

Small business16 of 114

under the label threshold

Mid-market35 of 110

under the label threshold

Enterprise21 of 93

under the label threshold

In email deliverability · each standing computed within its segment · bars are 0 to 100 · the accent bar is the product's own best reading

Standing by category

Every category where a model named Postmark for a mid-market B2B company. Share is first choices across the direct, paraphrase, budget and scale prompts; rank is within every product named in that category.

Category	Function	Share	Rank	Negative rate	Labels	Quadrant	Since September 2026
Email deliverability and testing tools	Marketing	0%	35 of 110	0%	4	under 10 labels · led by GlockApps at 34%

Movement

This is the first edition on this tier, so no move can be computed for Postmark yet. From the next edition this section shows, per buyer segment and per category, whether its share moved by more than the measured noise floor.

By model

How each model treated Postmark across every prompt where it was named for a mid-market B2B company. Fourteen models, six prompts per category.

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Model	Alternative	Mention	Labels
Claude Haiku 4.5	1	0	1
GPT-5.4 mini	0	0	0
Gemini 3.5 Flash	1	0	1
Perplexity Sonar	0	0	0
Grok 4.1 Fast	0	0	0
Mistral Small	0	0	0
DeepSeek V4 Flash	0	1	1
Llama 4 Maverick	0	0	0
Qwen 3.7 Flash	0	0	0
Kimi K2	0	0	0
GLM 4.7 FlashX	0	1	1
MiniMax M2.5	0	0	0
GPT-6 Luna	0	0	0
Muse Glimmer 30B	0	0	0

By framing

Which of the six questions produced the naming. By model says how often; this says asked what. The first-choice count on the right carries the marks of the models that produced it.

FramingLabels by classFirst choices

Direct2 labels1

Paraphrase0 labelsNone

Comparative6 labelsNone

Budget-constrained6 labelsNone

Scale-constrained5 labelsNone

Negative1 labelNone

First choiceAlternativeMentionNegative20 labels in all, every segment counted; 1 of the 1 first choices count toward share, since the comparative and negative framings do not. The bar is one segment per label class, to scale within the framing.

What the models said for it

Verbatim evidence the judge attached to positive labels.

“If your primary concern is developer-sent transactional emails and you want highly responsive, human support” Gemini 3.5 Flash · Email deliverability · scale prompt · alternative

“Postmark offers a free tier (100 emails/month); Basic plans start from $15/month” Claude Haiku 4.5 · Email deliverability · budget prompt · alternative

And against it

Verbatim evidence attached to negative labels. A warning on a product with few labels is a warning; on a product with many, it is one voice among them.

No model argued against it.

Named alongside

The products named in the same answers as Postmark, over the 20 answers that named it. Took the first choice instead counts the answers where the other product was the first choice and Postmark was named but was not.

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ProductSame answerTook the first choice insteadHead to head

GlockApps12 of 205Not among the top eight

Mailgun11 of 201Not among the top eight

SendGrid11 of 201Not among the top eight

MXToolbox10 of 201Not among the top eight

Validity Everest8 of 203Not among the top eight

Google Postmaster Tools6 of 202Not among the top eight

ZeroBounce6 of 201Not among the top eight

Mailtrap6 of 200Not among the top eight

Amazon SES5 of 201Not among the top eight

Litmus5 of 201Not among the top eight

A head-to-head page exists where both products are among a category's top eight. The other rows are the same fact without a page behind them, so they link to the product instead.

What carried it into the answer

The sites and pages cited by the answers that named Postmark. A fact about retrieval, not a lever on the model.

Citations exist only for the models that return a source list, five of the fourteen in this edition, so these counts come from 17 of the 20 answers that named Postmark and are not a share of its labels.

Domains cited

instantly.ai8

emailtooltester.com7

mailtrap.io7

omnisend.com7

smtp.com7

amplemarket.com6

myemailverifier.com6

overloop.com6

sender.net6

powerdmarc.com5

Sixty-five of the sixty-five domain citations in answers naming Postmark came from somebody else's page.

Pages cited

omnisend.com/blog/email-deliverability-tools7

amplemarket.com/blog/best-email-deliverability-tools6

emailtooltester.com/en/blog/best-email-deliverability-tools6

myemailverifier.com/blog/email-deliverability-tools6

overloop.com/blog/email-deliverability-tools5

smtp.com/blog/transactional-email/best-email-deliverability-tools5

instantly.ai/blog/email-deliverability-monitoring-tools4

mailercheck.com/articles/best-email-deliverability-tools4

Pages are listed as the models cited them.

What it publishes

ShowHide

Addresses on postmarkapp.com

1,024

subdomains included

Content

437

counted in the table below

Documentation

296

Product · Integration

0 · 22

Kind	Pages	Last 90 days	Latest
Blog	301	3	2026-09-08
Report or ebook	32	0	2017-10-19
Case study	30	0	2025-10-08
Podcast or video	26	0	2019-09-05
Glossary or explainer	19	0	2026-05-11
Webinar or virtual event	13	0	2025-12-08
Comparison	13	0	2025-03-27
News or press	2	undated
Conference or event	1	undated

Most recent

2026-09-08Restrict email sending api with ip allowlisting blog
2026-07-21The postmark mcp server one year later from 4 tools to 24 blog
2026-07-14Sending bulk email in python prioritize practices that get your mail delivered blog
2026-06-30Automate python emails with attachments that get delivered blog
2026-05-111010 how can i cancel my account glossary or explainer
2026-04-29Sending mission critical emails in python smtp or api blog

How it is countedHide how it is counted

Every page postmarkapp.com exposes, subdomains included. Kind is read from the address and title. The last 90 days, the latest date and the twelve months count pages by when they were published, from the site's feeds, a date in the address, or the page's own publication date, read from up to a hundred of its most recently changed pages; a page that says only when it last changed is counted in its kind but not in when, so the recent counts are a floor, and a kind none of whose pages gives a publication date reads undated. An event counts as online when its address or title says so (webinar, on demand, virtual or online summit); a conference, summit, trade show, expo or roadshow that does not say so is counted as a conference or event, which on a vendor's site is mostly in person. Read September 29, 2026.

Names read as Postmark

What the judge wrote, as written, with how often. The vendor table decides that these count as Postmark; a claim can dispute any of them.

Postmark (by ActiveCampaign) 1

Follow Postmark

An email the morning each edition publishes: where this product moved, where it held, and by how much against the noise floor. One address, confirmed by a click; a stop link in every email.

Already following? Everything you follow, with a stop for each.

The company

ActiveCampaign is the company behind Postmark.

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On record

Wikidata

Website: activecampaign.com
Headquarters: Chicago, United States
Founded: 2003
Also from ActiveCampaign: ActiveCampaign AI

Fetched September 14, 2026. These describe the company, not the product's standing, and a claimed page can dispute any of them. · Wikidata · Crunchbase

In its own words

Stated by the vendor, not checked

Positioning: Postmark is a fast and reliable transactional email service that delivers your application's emails on time, every time.
postmarkapp.com
For: developers
postmarkapp.com
Price stated: $15/month for 10,000 emails postmarkapp.com
Starting price: 15 postmarkapp.com
Free plan or trial: Start free trial postmarkapp.com
Certifications: GDPR complianceType 2 SSAE 16 SOC 1 accredited facilityPCI Level 1 Service Provider
Customers named: PaddleIndie HackersFaire.comIKEAlitmusdeskminecraftlivestream
Not stated on the pages read: Integrations, hosting

What Postmark's own pages state, read October 6, 2026: postmarkapp.com, postmarkapp.com/pricing, postmarkapp.com/security, postmarkapp.com/customers, postmarkapp.com/integrations. A claimed page can correct any of them.

Is this your product?

Claim this page

Claiming is free and changes nothing in the data. A claimed page shows a verified contact who is told when each edition publishes and when Postmark's standing changes by more than the noise floor; the right to propose corrections to the vendor table, meaning names the judge wrote that should or should not read as Postmark, applied by version and listed in the change log; and a one-line description supplied by the vendor and marked as such.

What a new claim receivesHide what a new claim receives

A new claim receives the current edition's vendor brief for Postmark by email, built from the raw record of the edition. It shows:

where Postmark is named, by buyer and by framing, and which cells hold its first choices;
the claims the models make when they name it, ranked, with the strongest and the weakest quoted;
its vocabulary against the segment leader's, and the pages the models cited;
who was chosen in the answers that did not name Postmark, and every reason the record gives;
a battlecard for each top rival: the head-to-head split, why they win, and the reservation quoted against them;
one page of published figures cleared to show a buyer.