Email Readability Analyser

For marketing emails, aim for a Flesch score between 60 and 80 — described as "standard" to "fairly easy" to read, equivalent to a 7th–9th grade reading level. Scores below 50 indicate text that is too complex for a broad audience. Scores above 80 are appropriate for very short, punchy emails. Avoid academic or technical language unless your audience specifically expects it.

Research consistently shows that emails between 50 and 200 words have the highest click-through rates. Very long emails (500+ words) see significant drop-off in reading completion. Transactional emails (receipts, confirmations) can be longer. The reading time estimate in this tool gives you an instant gut-check — most recipients will not spend more than 30–60 seconds on a marketing email.

Spam trigger words are phrases that spam filter algorithms associate with junk mail — "free offer", "act now", "click here", "guaranteed", "winner", "no cost", and similar. Having too many of them raises your spam score and increases the chance your email lands in the junk folder rather than the inbox. The analyser flags these words so you can rephrase or remove them before sending.

Keep average sentence length under 20 words. Short sentences are easier to scan on mobile devices, where most email is now opened. If you find your average is above 25 words, look for long sentences that can be split in two. Aim to vary sentence length — mixing short, punchy sentences with medium-length ones maintains rhythm and keeps readers engaged.

Spam filters evaluate text complexity and density as signals. Extremely short emails with few words but many links, or emails with dense technical jargon, can both raise spam scores. A well-structured email with a natural reading level, clear sentences, and no spam trigger words is more likely to pass through filters. Deliverability also depends on your sending reputation, SPF, DKIM, and DMARC — this tool focuses on the content side.