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Cold email subject line grader

'quick idea for {{company}}' grades A (100/100): it is 4 words, no spam words. Short, lower-case, specific subject lines like 'question about {{company}}' work best for cold email to cleaning company owners.

Updated 5 Nov 2026. Free, no account.

Result for

quick idea for {{company}}

A 100/100 grade A

Length4 words, 26 characters
Spam wordsnone
Marketing markersnone
ALL-CAPS wordsnone
Exclamation / question marks0 / 0
Emoji0
Merge fields{{company}}
Question or curiosityyes

Mobile preview

A phone inbox shows about the first 35 characters:

quick idea for {{company}}

Three rewrites

  1. quick idea grade it
  2. quick idea for {{company}} grade it
  3. question about quick idea grade it

20 cold email subject lines for cleaning companies

Lower case on purpose: a subject line that looks typed by a person gets opened like one. Merge fields match the 67Leads CSV.

  1. question about {{company}} grade
  2. {{company}} on google maps grade
  3. quick idea for {{company}} grade
  4. recurring clients at {{company}} grade
  5. {{first_name}}, quick question grade
  6. cleaning company in {{city}} grade
  7. idea for move-out cleans grade
  8. {{company}}'s google reviews grade
  9. {{company}} website grade
  10. commercial accounts in {{city}} grade
  11. noticed {{company}} on the map grade
  12. for the owner of {{company}} grade
  13. more recurring clients? grade
  14. {{city}} cleaning companies grade
  15. move-out cleans question grade
  16. saw {{company}} online grade
  17. {{first_name}}, commercial accounts? grade
  18. worth a look, {{first_name}}? grade
  19. {{company}} on google grade
  20. {{company}} in {{city}} searches grade

Which angle fits how many cleaning companies, counted live from the 67Leads warehouse:

How this works

The grade is rule-based and runs on the line you type. It starts at 100 and takes points off for length outside 2 to 6 words or over 45 characters, for phrases from the same 109-phrase list the spam word checker uses, for marketing markers (%, $, free, offer, sale), ALL-CAPS words, Title Case, exclamation marks, emoji, a fake "Re:" on a first email, and for a line with no merge field or no reason to open. A is 90 or more, F is under 60. The rewrites strip what cost points and keep your own words.

The idea lists use the trade names 67Leads carries and the offer angles from the cold email template generator. The angle counts are live from the warehouse.

Subject lines by trade

Tree service companiesRoofing contractorsHVAC contractorsInsulation contractorsPlumbersDentistsChiropractorsMed spasLaw firmsCleaning companiesPest control companiesElectricians

Need people to send it to?

67Leads lists US local businesses by trade and city, with emails read from each company's own website and labelled verified or not. The first 67 leads are free, no card.

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Questions

What makes a good cold email subject line?

Two to six words, under about 45 characters, lower case, specific to the business, and free of ad words like free, offer or limited time. 'question about {{company}}' beats 'Grow Your Business Today!!!'.

Does this predict my open rate?

No, and no tool can. Apple's Mail Privacy Protection loads messages on the user's behalf and stops senders from knowing when an email is opened, so open rates are inflated and unreliable (Apple, https://www.apple.com/newsroom/2021/06/apple-advances-its-privacy-leadership-with-ios-15-ipados-15-macos-monterey-and-watchos-8/, checked 4 Nov 2026). Judge a subject line by replies.

Should I use Re: or Fwd: in a cold email subject?

No. On a first email it pretends there was an earlier conversation. US law (CAN-SPAM) forbids misleading subject lines, and readers who notice stop trusting the rest.

Should cold email subject lines be lower case?

Usually. Lower case looks like a note from a person; Title Case and capitals look like a newsletter. Keep proper names capitalized if you prefer.

What are good cold email subject lines for roofers or other trades?

Ones about the business itself: its name, its listing, a job type it does. Pick a trade above for 20 ready lines with merge fields that match the 67Leads CSV.

Related free tools

Cold email spam word checkerEmail permutatorCold email template generatorSPF and DMARC checkerAll free tools

Lead lists and comparisons

Cleaning companies lead listsAll lead lists by tradeHow 67Leads compares67Leads vs Apollo