Lettergrowth uses Kit as their primary email service provider. Their email authentication setup is incomplete (score 50/100). Missing: DMARC, DMARC enforcement.
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 9 emails we've observed. DMARC policy is read live from DNS.
No DMARC record published. Domain is not protected against spoofing.
SPF alignment: observed emails use a third-party return-path (mail.n.convertkit.com) — SPF passes there but doesn't align with lettergrowth.com, so DMARC has to rely on DKIM alignment.
DKIM alignment: observed emails sign with a third-party DKIM key (n.convertkit.com) — DKIM passes there but doesn't align with lettergrowth.com, so DMARC has to rely on SPF alignment.
TLS: modern — 100% TLS 1.3 (across 13 sends).
Delivery: fast — 100% of emails in the last 7 days arrive in under 10 seconds (across 5 sends).
Brands often use multiple ESPs (e.g. one for marketing, another for transactional/notifications).
None — only the primary ESP(s) shown aboveESPs 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: lettergrowth.com, mail.n.convertkit.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 | 15 | 83.3% |
| promotions | 3 | 16.7% |
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 % |
|---|---|---|---|---|---|
| Kit | 14 | 78.6% | 21.4% | 0.0% |
Monthly 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 lettergrowth.com has been observed sending from, and where their mail landed in Gmail.
| IP | Hostname | Obs | Placement | Reputation |
|---|---|---|---|---|
| 149.72.60.6 | o47.ck.n.convertkit.com |
5 | 5 | Check → |
| 159.183.200.47 | o51.ck.n.convertkit.com |
3 | 2 | Check → |
| 149.72.193.89 | o48.ck.n.convertkit.com |
3 | 3 | Check → |
| 149.72.39.237 | o38.ck.n.convertkit.com |
2 | — | Check → |
| 149.72.176.45 | o30.ck.m.convertkit.com |
2 | — | Check → |
| 168.245.5.113 | o20.ck.n.convertkit.com |
2 | — | Check → |
| 168.245.126.179 | o4.ck.m.convertkit.com |
1 | — | Check → |
| Domain | ESPs detected | Delivery (7d) |
|---|---|---|
lettergrowth.com | Kit 20 |