Usepylon uses Customer.io for marketing email and Mailgun for transactional/notifications. They rank #12,020 in the Tranco list of most-popular domains. We've also observed sends via Postmark. Email goes out from 3 different subdomains. Their email authentication setup is solid (score 85/100). We've recorded 1 ESP change since first observing this brand.
Authentication signals observed in this brand's emails. SPF, DKIM and DMARC are the standard sender-authentication stack — see the DMARC policy below for whether spoofing is actually blocked or just monitored. One-click unsubscribe meets Google & Yahoo's bulk-sender requirements.
SPF / DKIM / DMARC above reflect the last 6 emails we've observed. DMARC policy is read live from DNS.
DMARC reports sent to usepylon.com. Policy
p=reject means receivers actively block or quarantine spoofed mail.
SPF alignment: all 7 observed emails use a return-path aligned with usepylon.com (pm-bounces.notifications.usepylon.com, cio114560.m.usepylon.com). SPF authenticates the visible From — supports DMARC directly.
DKIM alignment: all 14 observed emails sign with a domain aligned with usepylon.com (usepylon.com, notifications.usepylon.com, cio114560.m.usepylon.com). DKIM authenticates the visible From — supports DMARC directly.
TLS: 22% TLS 1.3, 78% TLS 1.2 (across 9 sends).
Delivery: fast — 100% of emails in the last 7 days arrive in under 10 seconds (across 3 sends).
Brands often use multiple ESPs (e.g. one for marketing, another for transactional/notifications).
Postmark 4ESPs we've seen sending email for this brand. Green = confirmed by SPF, sender IP rDNS, or known infra pairing (label shows the source). Grey = observed but not yet confirmed by SPF or PTR.
ESPs this brand has authorized in their SPF record. We confirm them with a green ✓ only after seeing recurring use (3+ emails across 2+ days). Until then they stay here — either we haven't observed any email yet, or we've seen a handful but not enough to call them a regular sender for the brand.
Probed: usepylon.com, pm-bounces.notifications.usepylon.com, cio114560.m.usepylon.com, notifications.usepylon.com, m.usepylon.com
Folder distribution across all emails from this brand observed in Gmail inboxes. High inbox % = good deliverability; spam appearances are the headline signal.
| Folder | Count | Share |
|---|---|---|
| inbox | 14 | 100.0% |
Which ESP's emails are landing where. Sorted by spam % so problem senders surface first. Brands using one ESP for marketing and another for transactional often see very different placement profiles per ESP. Per-ESP folder data only started being captured recently — counts here may be smaller than the total above until backfill catches up.
| ESP | Emails | Placement | Inbox % | Tabs % | Spam % |
|---|---|---|---|---|---|
| Customer.io | 3 | 100.0% | 0.0% | 0.0% | |
| Postmark | 4 | 100.0% | 0.0% | 0.0% | |
| Mailgun | 7 | 100.0% | 0.0% | 0.0% |
Daily observations per ESP. Brands often run multiple ESPs concurrently — marketing on one, transactional on another — so this chart shows usage rather than switches.
IP addresses usepylon.com has been observed sending from, and where their mail landed in Gmail.
| IP | Hostname | Obs | Placement | Reputation |
|---|---|---|---|---|
| 143.55.232.58 | v558.v5f06b487.use4.send.mailgun.net |
5 | 4 | Check → |
| 143.55.227.71 | v571.v54f91261.use4.send.mailgun.net |
3 | — | Check → |
| 104.245.209.237 | mta237b-ord.mtasv.net |
2 | — | Check → |
| 204.220.184.51 | k51.kb8c70eb.use4.send.mailgun.net |
2 | 1 | Check → |
| 104.245.209.201 | mta201a-ord.mtasv.net |
2 | 2 | Check → |
| Domain | ESPs detected | Delivery (7d) |
|---|---|---|
usepylon.com | Mailgun 7 | |
notifications.usepylon.com | Postmark 4 | |
m.usepylon.com | Customer.io 3 |