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Stonly

stonly.com
🏆Rank #25,472 🏷 SaaS 🇵🇱Poland

Stonly uses Customer.io as their primary email service provider. They rank #25,472 in the Tranco list of most-popular domains. Their email authentication setup is solid (score 95/100).

Marketing ESPCustomer.io
Total observations4
Active days3
Avg per active day1.3
Last activity⏸ Slowing · 3 weeks ago
Cadence~weekly
Compare Stonly with another brand:

Email setup 95/100

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.

Strong email setup
Authentication is in good shape — SPF, DKIM, and DMARC enforcement all configured.
95/100
SPF
pass
DKIM
pass
DMARC
pass (reject)
BIMI
pass
Unsubscribe
one-click
SPF lookups 4/10
Authentication

DMARC reports sent to stonly.com. Policy p=reject means receivers actively block or quarantine spoofed mail.

SPF alignment: all 4 observed emails use a return-path aligned with stonly.com (cioeu53926.stonly.com). SPF authenticates the visible From — supports DMARC directly.

DKIM alignment: all 3 observed emails sign with a domain aligned with stonly.com (cioeu53926.stonly.com). DKIM authenticates the visible From — supports DMARC directly.

Other ESPs detected

Brands often use multiple ESPs (e.g. one for marketing, another for transactional/notifications).

None — only the primary ESP(s) shown above

Confirmed senders

ESPs 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.

Customer.io ✓ via Mailgun

Other SPF authorizations

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.

Google Workspace Mailgun SendGrid

Probed: stonly.com, cioeu53926.stonly.com

Where emails landed (Gmail)

Folder distribution across all emails from this brand observed in Gmail inboxes. High inbox % = good deliverability; spam appearances are the headline signal.

FolderCountShare
inbox 4 100.0%

Placement by ESP

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 4
100.0% 0.0% 0.0%

ESP activity over time

May 20 – Jun 11, 2026 · 3 days with sends

Daily observations per ESP. Brands often run multiple ESPs concurrently — marketing on one, transactional on another — so this chart shows usage rather than switches.

2 0 Customer.io: 1 (2026-05-20)1Customer.io: 2 (2026-06-04)2Customer.io: 1 (2026-06-11)105/2005/2305/2605/2906/0106/0406/0706/10
Customer.io

Similar brands using Customer.io

Sending IPs

IP addresses stonly.com has been observed sending from, and where their mail landed in Gmail.

IPHostnameObsReputation
161.38.205.175 v5175.v5b52dc11.euw1.send.eu.mailgun.net 3 Check →
141.193.33.180 v5180.v5c07f50a.euw1.send.eu.mailgun.net 1 Check →

Per-IP inbox / promotions / spam is being collected and will appear here as new emails are observed.

Sending domains

DomainESPs detectedDelivery (7d)
stonly.comCustomer.io 4