Email Tools
Free tools for email deliverability and cold outreach. Test subject lines, check full email spam scores, validate SPF and DKIM records, and generate DMARC policies. No account required.
Available now
Free tools you can use right now, no signup required.
Cold Email Subject Line Tester
Score your cold email subject lines for spam words, length, and open rate potential.
Open toolSPF DKIM DMARC Checker
Check your domain SPF, DKIM, and DMARC DNS records with color-coded results and plain-English explanations.
Open toolDMARC Record Generator
Generate a valid DMARC TXT record for your domain with plain-English explanations for every setting.
Open toolEmail Spam Score Checker
Check your email subject and body for spam trigger words, formatting issues, and deliverability risks.
Open toolEmail Duplicate Checker
Find and remove duplicate emails from your lead lists. Upload a blocklist and leads CSV to get a clean unique list ready for cold email campaigns.
Open toolEmail Deliverability Checker
Check your domain SPF, DKIM, and DMARC DNS records instantly. Get a 0-100 deliverability score with actionable fixes for every issue. Free, no signup.
Open toolWhat email deliverability actually means
Deliverability is the percentage of sent emails that land in the inbox rather than spam or the promotions tab. A 70% deliverability rate sounds acceptable until you realize 3 in 10 messages never get seen. For cold outreach, that math kills campaigns before they start.
The biggest factors are domain authentication (SPF, DKIM, and DMARC records), sender reputation, and subject line content. You can write the best cold email in the world and still see zero replies if your domain fails authentication checks. Fix the technical foundation first, then optimize copy.
Subject lines carry more weight than most people expect. Spam filters score each word, the total character count, and punctuation patterns before the email reaches a human. A subject line with "FREE!!!" in all caps fails on three separate signals simultaneously. Testing before sending takes 30 seconds and removes that risk entirely.
More email tools coming soon.
Email tools: frequently asked questions
What is email deliverability?
Email deliverability is the ability of your emails to reach the inbox instead of the spam folder. It depends on your domain reputation, SPF and DKIM authentication records, sending volume, and subject line content. Poor deliverability means even well-written emails never get seen.
What is a cold email subject line tester?
A cold email subject line tester scores your subject line for spam trigger words, character length, and open rate potential before you send. It flags terms that spam filters commonly reject and suggests changes that improve inbox placement and click-through rates.
What are SPF, DKIM, and DMARC records?
SPF, DKIM, and DMARC are DNS records that authenticate your email sending domain. SPF lists which mail servers are allowed to send on your behalf. DKIM adds a cryptographic signature to each message. DMARC tells receiving servers what to do when authentication fails. Missing or misconfigured records are the leading cause of cold emails landing in spam.
How long should a cold email subject line be?
Cold email subject lines perform best between 30 and 50 characters. Shorter than 20 characters often lacks context. Longer than 60 characters gets cut off on mobile screens, where over 60% of emails are read. Personalized subject lines with the recipient name outperform generic ones by 26%.
What words trigger spam filters in email subject lines?
Common spam trigger words in subject lines include "free", "urgent", "act now", "limited time", "guarantee", "100%", "earn money", and excessive punctuation like multiple exclamation marks. All-caps words also raise spam scores. The cold email subject line tester flags these automatically.
Are these email tools free?
Yes. All email tools on Vortenza are completely free with no account required. The cold email subject line tester runs entirely in your browser. No email is sent and no data is stored.