How to Measure an Envelope

Sep 5, 2022

Are you looking to send out mailings or marketing materials in envelopes but are unsure of how to measure them accurately? At Shout It Marketing, we understand the importance of getting your envelopes just right for a professional and polished appearance. Let us guide you through how to measure an envelope effectively.

Envelope Size Guide

Envelopes come in various standard sizes, such as #10, A4, A5, and more. To measure an envelope correctly, you should consider the following dimensions:

  • Length: Measure the longest side of the envelope.
  • Width: Measure the shorter side of the envelope.
  • Flap: Measure the length of the flap when it is closed.
  • Gusset: If your envelope has a gusset, measure its depth.

Why is Measuring Envelopes Important?

Accurate measurements of envelopes are crucial for several reasons:

  • Postage: Incorrectly sized envelopes may result in higher postage costs.
  • Professionalism: Well-fitted envelopes enhance the professional image of your mailings.
  • Compatibility: Ensuring the right size is essential for compatibility with inserts or contents.

Steps to Measure an Envelope

  1. Length and Width: Use a ruler or measuring tape to determine the length and width of the envelope in inches or millimeters.
  2. Flap Measurement: Include the flap in your measurements to get an accurate size for sealing.
  3. Gusset Width: If applicable, measure the gusset width for expansion capacity.

Choosing the Right Envelope Size

Based on your measurement, select an envelope size that fits your needs best. Common envelope sizes cater to different contents and purposes:

  • #10 Envelopes: Ideal for letters and standard business correspondence.
  • A4 Envelopes: Suited for documents and letters that are A4 in size.
  • A5 Envelopes: Perfect for smaller documents like invitations or cards.

Custom Envelope Options

If your mailing requires unique dimensions or branding, consider custom envelope options. Tailored envelopes can showcase your brand identity and offer a personalized touch to your communications.


Measuring an envelope accurately is essential for efficient mailing processes and a professional presentation. At Shout It Marketing, we specialize in optimizing your business communications, including envelope measurement and customization. Contact us today to elevate your mailing strategies!