Email header analyzer
Paste raw headers to map delivery hops, delays, and SPF/DKIM/DMARC results.
This email header analyzer takes the raw headers you paste and reconstructs the path a message traveled, listing each Received hop in order with the time spent at every stage. It surfaces where delays crept in, which servers handled the message, and how the SPF, DKIM, and DMARC checks resolved at the receiving end. That makes it straightforward to diagnose slow delivery or figure out why a message landed in spam. Everything runs in your browser-facing tool with nothing stored, so you can analyze as many messages as you need.
Frequently asked questions
Where do I find the raw email headers?
Most clients expose them under an option like "Show original," "View source," or "Message details." Copy the full block from the top of the message and paste it in.
Why are there delays between hops?
Each Received line is timestamped, and large gaps usually point to greylisting, queue backups, or a slow relay. The analyzer highlights the longest gaps so you can focus there.
What do the SPF, DKIM, and DMARC results mean here?
They show how the receiving server judged authentication for this specific message, which explains pass, fail, or neutral outcomes that affect placement.
How do I read the Received headers?
Read them bottom to top — the lowest Received line is the first server (the sender), and each line above is the next hop. The analyzer reverses them into delivery order for you.
What does the Return-Path tell me?
It's the envelope sender, where bounces go, and it's what SPF is actually checked against — not the visible From address. A mismatch between the two is common and is why DMARC alignment matters.
Why does the time spent in one hop look huge?
Clock differences between mail servers can make a single hop appear to take negative or inflated time. Treat individual hop times as approximate and focus on consistently large gaps, which usually mean greylisting or a queue.
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