How to Check Sentence Length in an Email (and Where to Split Long Ones)

To check sentence length in an email, count the words in each sentence and compare them with a limit you choose. The email sentence length checker does the counting: paste the email and it lists every sentence with its word count, the average and the longest, and marks the ones over your limit with the place where each can break.

No mailbox provider publishes a sentence limit, so the limit is yours. The point is readability: a reader on a phone, between other messages, owes you no effort.

The by-hand way

1. Read the email aloud. Wherever you run out of breath, mark the sentence.
2. Count the words in each marked sentence. A word is a run of letters and digits, so follow-up and don't each count as one.
3. Pick a limit, often around 20 words, and circle everything above it.
4. For each circled sentence, find a joining word (and, but, so, because, which) and see whether two real sentences stand on either side of it.

This works, but for a 150-word email it is slow, and counting by eye is where mistakes creep in.

Step 1: paste the email

Paste the email text. A full stop, question mark or exclamation mark followed by a space ends a sentence, and so does a line break. Short forms such as Mr., Dr. and e.g. do not end one. A short line with no end mark, such as the greeting or your name under the email, is read as a greeting or sign-off and left out of the counts.

Step 2: set your limit

The box starts at 20 words. Change it to the length you want to hold yourself to. Nothing checks the number for you; it is a personal rule, so use the one you would apply when reading your own email aloud.

Step 3: read the list

Column	What it shows
Sentence	The text as written
Words	The word count
Over limit	Marked when the count is above your limit
Split point	The joining word where a new sentence could start

At the top you get the number of sentences, the average length and the longest one.

How the split points are found

For each sentence over your limit, the tool looks for and, but, so, because, which, while, although, then, however, also and plus, and for semicolons. A point is shown only when at least four words stand on each side, so a split leaves two real sentences. It follows a rule on the words as written and does not understand the sentence, so pick the points that read well or cut a clause instead.

Step 4: split, then paste again

Rewrite the marked sentences in your own words and paste the email in again. Nothing is rewritten for you. For paragraph shape, use the email paragraph length checker; for the whole email in one pass, the cold email copy checker. More on structure is in cold email templates.

What this check cannot do

• It counts words as written. It does not judge whether a short sentence is clear.
• Abbreviations outside a short built-in list may end a sentence early.
• The joining word list is English only.
• Subject lines, lists and tables are read like any other text.

Before you send, verify the list

Before you send, verify the list at the verify page: the first 100 email checks are free with a Google sign-in, no card. Each address comes back valid, risky or invalid with a reason, and nothing is sent to anyone on the list. A well-edited email still bounces if the address is dead. For larger or recurring lists, see bulk email verification, list cleaning and pricing.

Check your email now

Paste it into the email sentence length checker.