Kozan Digital Agency

    3 Free Email Tools in One

    Free Email Marketing Toolkit

    The email marketing toolkit for pros. Test subject lines, check spam scores, and generate preheaders — everything you need before hitting send.

    No signupSubject line testerSpam checkerPreheader generator

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    Kozan manages full email marketing strategies - from list building and automation to campaigns that convert.

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    What is the Email Marketing Toolkit?

    The Email Marketing Toolkit bundles three free utilities every email marketer needs before hitting send: a subject line tester that scores length, power-word usage, and predicted open-rate potential; a spam score checker that flags trigger words, all-caps phrases, and other deliverability red flags; and a preheader generator that produces high-performing preview text for any campaign. Together, they catch the small mistakes that quietly destroy open rates and inbox placement.

    Who it's for

    Email marketers, CRM managers, and growth teams running newsletters or lifecycle campaigns — especially anyone shipping to lists above 5,000 subscribers where small deliverability issues compound. Agencies use it to QA client emails before scheduling, and founders use it to sanity-check launch announcements before they hit a list of customers.

    How to use it

    Pick the tab you need. For the subject line tester, paste your draft subject and review the feedback on length, sentiment, and likely open-rate impact. For the spam checker, paste subject and body to see flagged terms. For preheaders, enter your subject and topic and choose from the generated options. Run all three before every major send. If your open rates still aren't moving, Kozan helps with full email-marketing programmes — strategy, design, automation, and analytics.

    What the tools check and why it matters

    The subject line tester scores five factors: character length across mobile and desktop preview panes, power-word density, question framing, emoji usage, and readability at a glance. These map directly to what inbox clients render before a subscriber decides to open. The spam score checker scans for patterns that trigger popular content filters — phrases associated with phishing, excessive capitalisation, suspicious punctuation, and monetary claims without context. These checks do not replace deliverability infrastructure (SPF, DKIM, sender reputation, list hygiene) but they catch the copy-level mistakes that quietly drag placement before a technical issue is ever suspected. The preheader generator creates complementary preview text that works as a second hook alongside the subject line — most email clients show 80–120 characters of preheader, and strong preheaders reliably lift open rates by 5–15% without changing anything else in the send. Running all three tools takes under five minutes and eliminates the most common pre-send mistakes in one pass.

    Email Marketing Toolkit FAQ

    Common questions about the free subject line tester, spam checker, and preheader generator.

    Yes — the subject line tester, spam score checker, and preheader generator are all free, no signup, no usage limits. Everything runs in your browser.

    No. Everything you paste — subject lines, body copy — stays in your browser session. Nothing is sent to our servers and nothing is logged.

    It's a directional check based on well-known spam triggers — high-risk words, all-caps phrases, excessive punctuation, and other common deliverability red flags. It won't catch domain-level issues (DKIM, SPF, sender reputation) but it will catch the content-level mistakes that quietly hurt placement.

    Generally 30–50 characters for desktop preview, 25–35 for mobile preview. The tester scores both and flags subject lines that risk truncation. Punchy is more important than short.

    The preheader is the preview text that appears next to the subject in the inbox. It typically pulls from the first line of your email if you don't set it explicitly. A strong preheader can lift open rates 5–15% by giving recipients a second hook beyond the subject.

    Yes. Agencies and freelancers use it to QA campaigns before scheduling. It's also useful for sanity-checking automated email flows after copy updates.

    Content is one piece. Deliverability also depends on sender reputation, list hygiene, send time, and segmentation. Kozan builds full email programmes — strategy, automation, design, and reporting — if open rates aren't moving after content fixes.