Open rate (email)

What is email open rate?

Email open rate is the percentage of successfully delivered emails that are opened by the recipient — calculated as (emails opened ÷ emails delivered) × 100. It is typically tracked by loading a 1×1 tracking pixel in the email body: when the email is opened and images load, the pixel fires and the open is recorded.

For cold email senders, open rate measures two things: whether your subject line and sender name are compelling enough to get a click, and whether your emails are landing in inbox (spam-filtered emails rarely get opened). Open rate is the top-of-funnel metric — it tells you whether the email is being seen. Reply rate and meeting rate tell you whether it's working.

Open rate became a less reliable metric after Apple's Mail Privacy Protection (MPP) update in September 2021, which pre-loads email content — including tracking pixels — regardless of whether the recipient actually opens the email. This inflated reported open rates for Apple Mail users by 20–40 percentage points. For cold email, this means reported open rates above 60–70% may include large numbers of MPP ghost opens that don't reflect genuine human engagement.

What drives open rate in cold email

Four factors determine whether a cold email gets opened, in approximate order of influence:

• Deliverability — an email in the spam folder is not opened, regardless of subject line quality. This is why deliverability work comes before subject line testing. If inbox placement drops from 90% to 70%, open rate drops proportionally — not because the subject line changed, but because fewer people see it.
• Sender name — the 'From' name is often the first thing a prospect reads. A company name ('Gangly') performs worse than a person's name ('Jake at Gangly') for cold outreach. First name only ('Jake') tests well for some audiences. Test your sender name as a variable.
• Subject line — controls whether a recipient who sees the email actually clicks to open it. Best-performing cold email subjects for B2B outbound: short (under 50 chars), specific (includes the prospect's company or a concrete observation), curiosity-driven or direct, and free of spam-trigger words (free, sale, limited time, guaranteed).
• Preview text — the first 75–140 characters of the email body that appear in the inbox preview pane. Often ignored in cold email, but it's free real estate that extends the subject line's message. 'Jake at Gangly — quick question about your SDR team' subject + 'I saw you just hired 6 new BDRs — there's usually one specific bottleneck at that stage...' preview is a complete pitch in 2 lines.

Open rate benchmarks for cold email

Cold email open rate benchmarks by industry and personalization level. Note: these figures reflect observed rates in sending platforms and may include MPP ghost opens for Apple Mail users.

Sources: Lemlist Cold Email Benchmark Report 2024, HubSpot Email Marketing Statistics 2024, Mailchimp Email Benchmarks 2024 (all delivery types), Salesloft State of Sales Email 2023. All figures approximate due to MPP tracking impact.

Open rate vs reply rate: which matters more

Reply rate is a more reliable performance indicator than open rate for cold email. Open rate is inflated by MPP ghost opens and doesn't reflect whether the recipient read and engaged with the content. Reply rate is not affected by MPP — a reply requires genuine human action.

A sequence with 60% open rate and 0.5% reply rate has a message problem — people are opening but not engaging. A sequence with 30% open rate and 8% reply rate has a strong message that converts the readers it gets. Focus optimization effort on reply rate once open rate is above ~25–30%.

Meeting booked rate (replies that convert to calls) is the metric that ultimately connects to pipeline. Track open → reply → meeting as a conversion funnel, not open rate as a standalone KPI.

How Gangly influences open rate

Gangly's Outreach Writer generates subject lines and first-touch messages tied to the specific signal that triggered the outreach. A subject line that references the prospect's recent company news ('New VP of Sales at [Company]') outperforms generic subjects because it answers the prospect's immediate question — 'why is this email relevant to me today?' — from the inbox view.

The rep's send comes from their own connected Gmail or Outlook inbox — not a mass sending domain — which maintains the sender name recognition and domain authority that support higher open rates over time.

See how Outreach Writer works →

Frequently asked questions