Prolific uses Customer.io for marketing email and SendGrid for transactional/notifications. They rank #13,879 in the Tranco list of most-popular domains. Their email authentication setup is good (score 70/100). Missing: one-click unsubscribe. We've recorded 2 ESP changes 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 10 emails we've observed. DMARC policy is read live from DNS.
DMARC reports sent to prolific.com. Policy
p=reject means receivers actively block or quarantine spoofed mail.
SPF alignment: all 175 observed emails use a return-path aligned with prolific.com (em2830.prolific.com, outbound-eu.intercom.prolific.com, cioeu110962.prolific.com). SPF authenticates the visible From — supports DMARC directly.
DKIM alignment: all 168 observed emails sign with a domain aligned with prolific.com (prolific.com). DKIM authenticates the visible From — supports DMARC directly.
TLS: modern — 94% TLS 1.3 (across 81 sends).
Delivery: fast — 100% of emails in the last 7 days arrive in under 10 seconds (across 57 sends).
Brands often use multiple ESPs (e.g. one for marketing, another for transactional/notifications).
Intercom 6ESPs 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: prolific.com, em2830.prolific.com, cioeu110962.prolific.com, outbound-eu.intercom.prolific.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 | 65 | 90.3% |
| promotions | 7 | 9.7% |
Placement observed in Outlook / Microsoft 365 mailboxes. Focused Inbox splits mail into two tabs, "Focused" (inbox) and "Other", plus Junk. 89% reached the Focused inbox across 35 observed emails.
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 | 2 | 100.0% | 0.0% | 0.0% | |
| Intercom | 5 | 100.0% | 0.0% | 0.0% | |
| SendGrid | 60 | 88.3% | 11.7% | 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 prolific.com has been observed sending from, and where their mail landed in Gmail.
| IP | Hostname | Obs | Placement | Reputation |
|---|---|---|---|---|
| 159.183.222.82 | wfbtdzrn.outbound-mail.sendgrid.net |
66 | 11 | Check → |
| 167.89.75.236 | o1678975x236.outbound-mail.sendgrid.net |
63 | 8 | Check → |
| 159.183.33.20 | wfbtnkkq.outbound-mail.sendgrid.net |
44 | 2 | Check → |
| 147.253.221.179 | mta-221-179.sparkpostmail.com |
5 | 1 | Check → |
| 198.244.60.102 | a102.a5d06dfa.euw1.send.eu.mailgun.net |
2 | — | Check → |
| 185.250.238.78 | v578.v5bda8fb2.euw1.send.eu.mailgun.net |
1 | — | Check → |
| 147.253.221.176 | mta-221-176.sparkpostmail.com |
1 | — | Check → |
| Domain | ESPs detected | Delivery (7d) |
|---|---|---|
prolific.com | SendGrid 173 Intercom 6 Customer.io 3 |
