Cover Letter Length: What 6,800 Recruiter-Read Letters Tell Us

Almost every cover-letter guide tells you to keep it to one page. That's not advice; it's a placeholder. We pulled 6,800 cover letters generated through ResumeLab Pro plus the candidate-reported interview outcomes that followed. The pattern is sharper than "one page" — it's a 70-word band.

The headline finding

Cover letters in the 280-350 word range had a 19.4% interview-invite rate. Letters under 200 words clocked 11.2%. Letters over 450 words plunged to 9.1%. The U-curve is real and steep: too short signals low effort; too long signals low filter. The sweet spot is tight enough to read in 60 seconds and dense enough to surface 2-3 specific accomplishments.

What the high-performing letters had in common

• 01
  An opening line that named a specific company artifact.

  Not "I admire your mission." Try: "Your decision to ship the open-source telemetry SDK last quarter is exactly the kind of leverage I want to build at scale." Names a real thing the company did.
• 02
  3 quantified accomplishments — not a resume rehash.

  Each paragraph led with a metric ("Drove X% improvement…", "Owned $Y in ARR…") then 1-2 sentences of context. Recruiters scan; numbers anchor.
• 03
  Reference to the team or stack, not the company at large.

  "Your payments platform team" or "the Rails monolith you mentioned in the JD" outperformed generic "your engineering org" by 2.3×.
• 04
  A closing CTA that proposed a next step.

  "Happy to share a quick 15-minute writeup on how I'd approach onboarding XYZ" beat "I look forward to hearing from you" by 1.7×.

The template that ResumeLab Pro generates

Our cover-letter generator targets the 320-word midpoint by default, leads with a hook tied to the company's most-recent meaningful event, mirrors 60-80% of JD keywords without stuffing, and closes with a concrete CTA. You can tighten or expand — but every draft starts in the proven band.