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Respondent

respondent.io
🏆Rank #101,337 🏷 Marketing & Agencies 🇵🇱Poland

Respondent uses Mailgun as their primary email service provider. They rank #101,337 in the Tranco list of most-popular domains. We've also observed sends via Mailjet. Their email authentication setup is solid (score 85/100).

Transactional ESPMailgun
Total observations5
Active days5
Avg per active day1.0
Last activity📬 Active · 5 days ago
Cadence~weekly
Compare Respondent with another brand:

Email setup 85/100

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.
85/100
SPF
pass
DKIM
pass
DMARC
pass (reject)
BIMI
none
Unsubscribe
one-click
SPF lookups 10/10

SPF / DKIM / DMARC above reflect the last 3 emails we've observed. DMARC policy is read live from DNS.

Authentication

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

SPF alignment: 80% of observed emails use an aligned return-path (notifications.respondent.io); the rest use third-party paths (a3092884.bnc3.mailjet.com) where DMARC has to rely on DKIM alignment.

DKIM alignment: all 5 observed emails sign with a domain aligned with respondent.io (notifications.respondent.io, respondent.io). DKIM authenticates the visible From — supports DMARC directly.

Transport & deliverability

Delivery: fast — 100% of emails in the last 7 days arrive in under 10 seconds (across 2 sends).

Other ESPs detected

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

Mailjet 1

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.

Mailgun ✓ confirmed Mailjet ✓ confirmed

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 HubSpot SendGrid

Probed: respondent.io, notifications.respondent.io, a3092884.bnc3.mailjet.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 3 100.0%

Where emails landed (Outlook)

Placement observed in Outlook / Microsoft 365 mailboxes. Focused Inbox splits mail into two tabs, "Focused" (inbox) and "Other", plus Junk. 100% reached the Focused inbox across 2 observed emails.

Focused 100% (2) Junk 0% (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 %
Mailgun 2
100.0% 0.0% 0.0%
Mailjet 1
100.0% 0.0% 0.0%

ESP activity over time

Jun 2 – Jun 26, 2026 · 4 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.

1 0 Mailjet: 1 (2026-06-02)1Mailgun: 1 (2026-06-19)1Mailgun: 1 (2026-06-24)1Mailgun: 1 (2026-06-26)106/0206/0506/0806/1106/1406/1706/2006/2306/26
Mailgun Mailjet

Similar brands using Mailgun

Sending IPs

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

IPHostnameObsPlacementReputation
198.244.49.234 a234.a6e4cdb8.use4.send.mailgun.net 4 1 Check →
45.14.148.98 o98.p40.mailjet.com 1 Check →

Sending domains

DomainESPs detectedDelivery (7d)
respondent.ioMailgun 4 Mailjet 1