Tooltester uses Kit for marketing email and Mailtrap for transactional/notifications. They rank #185,803 in the Tranco list of most-popular domains. We've also observed sends via 2 other providers: Brevo, Mailchimp. Their email authentication setup is good (score 80/100). We've recorded 12 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 cloudflare.net. Policy
p=quarantine means receivers actively block or quarantine spoofed mail.
SPF alignment: 98% of observed emails use an aligned return-path (ckespa.tooltester.com, mt81.tooltester.com); the rest use third-party paths (gb.d.sender-sib.com) where DMARC has to rely on DKIM alignment.
DKIM alignment: all 129 observed emails sign with a domain aligned with tooltester.com (tooltester.com). DKIM authenticates the visible From — supports DMARC directly.
TLS: modern — 100% TLS 1.3 (across 49 sends).
Delivery: fast — 100% of emails in the last 7 days arrive in under 10 seconds (across 12 sends).
Brands often use multiple ESPs (e.g. one for marketing, another for transactional/notifications).
Brevo 3 Mailchimp 2ESPs 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: tooltester.com, ckespa.tooltester.com, mt81.tooltester.com, gb.d.sender-sib.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 | 157 | 98.1% |
| promotions | 3 | 1.9% |
Placement observed in Outlook / Microsoft 365 mailboxes. Focused Inbox splits mail into two tabs, "Focused" (inbox) and "Other", plus Junk. 30% reached the Focused inbox across 10 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 % |
|---|---|---|---|---|---|
| Brevo | 3 | 66.7% | 33.3% | 0.0% | |
| Kit | 103 | 100.0% | 0.0% | 0.0% | |
| Mailtrap | 27 | 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 tooltester.com has been observed sending from, and where their mail landed in Gmail.
| IP | Hostname | Obs | Placement | Reputation |
|---|---|---|---|---|
| 149.72.61.159 | o46.ck.n.convertkit.com |
22 | 3 | Check → |
| 149.72.193.89 | o48.ck.n.convertkit.com |
21 | 2 | Check → |
| 149.72.39.237 | o38.ck.n.convertkit.com |
16 | 1 | Check → |
| 149.72.158.9 | o27.ck.m.convertkit.com |
14 | 4 | Check → |
| 149.72.60.6 | o47.ck.n.convertkit.com |
12 | — | Check → |
| 149.72.176.45 | o30.ck.m.convertkit.com |
11 | 1 | Check → |
| 45.158.83.28 | smtp-83-28.mailtrap.live |
10 | — | Check → |
| 168.245.126.179 | o4.ck.m.convertkit.com |
10 | 4 | Check → |
| 192.254.115.187 | o42.ck.n.convertkit.com |
9 | — | Check → |
| 45.158.83.1 | smtp-83-1.mailtrap.live |
8 | 2 | Check → |
| 159.183.200.47 | o51.ck.n.convertkit.com |
7 | 1 | Check → |
| 45.158.83.25 | smtp-83-25.mailtrap.live |
4 | — | Check → |
| 45.158.83.27 | smtp-83-27.mailtrap.live |
4 | — | Check → |
| 45.158.83.7 | smtp-83-7.mailtrap.live |
4 | 1 | Check → |
| 44.192.35.10 | mail-usn11.freshemail.io |
3 | — | Check → |
| 168.245.5.113 | o20.ck.n.convertkit.com |
3 | — | Check → |
| 45.158.83.2 | smtp-83-2.mailtrap.live |
3 | — | Check → |
| 77.32.148.2 | gb.d.sender-sib.com |
3 | — | Check → |
| 45.158.83.4 | smtp-83-4.mailtrap.live |
1 | — | Check → |