Email Detective — ESP Tracker

Workweek

workweek.com ↗

🏆Rank #424,911 🏷 SaaS ✓ Inbox 100%

Workweek uses Sailthru for marketing email and Postmark for transactional/notifications. They rank #424,911 in the Tranco list of most-popular domains. Their email authentication setup is good (score 73/100). Missing: DMARC enforcement.

Marketing ESPSailthru

Transactional ESPPostmark

Total observations55

Active days30

Avg per active day1.8

Last activity📬 Active · 2 days ago

Cadence~every 2 days

Other technologies

Non-ESP tools detected in this brand's emails. Independent of who sends — a brand can use any combination.

HTML builder

Beefree SDK

Email setup 73/100

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.

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=none is monitor-only — receivers won't act on spoofing yet.

SPF alignment: 6% of observed emails use an aligned return-path (pm-bounces.workweek.com); the rest use third-party paths (mx.sailthru.com) where DMARC has to rely on DKIM alignment.

DKIM alignment: all 38 observed emails sign with a domain aligned with workweek.com (workweek.com). DKIM authenticates the visible From — supports DMARC directly.

TLS: modern — 100% TLS 1.3 (across 15 sends).

Delivery: fast — 89% of emails in the last 7 days arrive in under 10 seconds (across 9 sends).

Other ESPs detected

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

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.

Postmark ✓ confirmed Sailthru ✓ 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

Probed: workweek.com, mx.sailthru.com, pm-bounces.workweek.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.

Where emails landed (Outlook)

Placement observed in Outlook / Microsoft 365 mailboxes. Focused Inbox splits mail into two tabs, "Focused" (inbox) and "Other", plus Junk. 67% reached the Focused inbox across 3 observed emails.

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.

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

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Sending IPs

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

Sending domains