Email Subject Line Scorer
Enter your email subject and get an open-rate score with specific improvement tips.
0 characters — ideal is 40–60
Click to test these examples
Email Subject Lines: The #1 Factor in Email Open Rates
Email subject lines determine 47% of email open rates — they are the most impactful element of any email campaign, yet most professionals write them as an afterthought. The average office worker receives 121 emails per day and spends only 3–4 seconds deciding whether to open each one. Our subject line scorer analyses power words, length, personalisation signals, spam triggers and curiosity gaps to give you an actionable open rate prediction.
Frequently Asked Questions
What makes a good email subject line? ▼
High-performing subject lines: are 40–60 characters long, include the recipient's name or "you/your" (personalisation), create curiosity or urgency, include a specific number ("3 ways to..."), avoid spam trigger words (free, winner, urgent, !!!), avoid ALL CAPS, and clearly indicate value to the reader in the first few words.
What are email spam trigger words to avoid? ▼
High-risk spam triggers: Free, Buy now, Click here, Order now, Urgent, Winner, Congratulations, Guaranteed, No obligation, Risk-free, Act now, Limited time, Earn money, Make money, Increase sales, !!!, $$$, 100% free. Using even 1–2 of these in a subject line can significantly reduce deliverability.
What is the best time to send marketing emails in India? ▼
For B2B India: Tuesday–Thursday, 9–11 AM or 2–4 PM IST. For B2C/e-commerce: Tuesday, Thursday, weekend mornings. Avoid Monday mornings (inbox overwhelm) and Friday afternoons (pre-weekend). Test with your specific audience — these are starting benchmarks, not universal rules.
How to A/B test email subject lines? ▼
Send version A to 20% of your list, version B to another 20%, wait 4 hours and check open rates. Send the winner to the remaining 60%. Most email platforms (Mailchimp, Klaviyo, Zoho Campaigns) support automated A/B testing. Test one variable at a time: subject length, emoji presence, question vs statement, personalisation.
Do emojis in email subject lines improve open rates? ▼
Research is mixed — for B2C brands targeting millennials: emojis at the beginning of subjects can increase open rates by 25–29%. For B2B professional audiences: emojis often decrease open rates and trust. Rule of thumb: use 1 relevant emoji for casual/consumer brands; avoid for formal B2B communication.