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CHOOSING A DOMAIN EXTENSION

The Definitive Guide

8 chapters Last updated 21 September 2026 Free to read, no account

Almost everything written about choosing a domain extension is written by somebody who sells domain extensions, which is why it reads as a list of options rather than a set of consequences.

The choice is an operational decision more than a branding one. Extensions differ on renewal cost, eligibility rules, recovery windows after expiry, deliverability reputation, and in two cases whether your site loads at all without a valid certificate.

This guide covers what actually differs, what it costs you later, and which considerations are real versus which are marketing.

In this guide you will learn:

  • Which extensions have eligibility rules that can strip a domain
  • Why .app and .dev fail completely rather than warning
  • How renewal pricing differs from registration pricing, and by how much
  • Which extensions carry a deliverability penalty
  • Which have short or nonexistent recovery windows
  • When holding several is worth it and when it is theatre

Contents

1

What actually differs

Six things vary between extensions, and none of them are aesthetic.

2

Eligibility and residency

The rules that can cost you a domain independently of renewal.

3

Price now versus price later

First-year discounts, premium renewals, and the gap.

4

Recovery after expiry

Some registries are forgiving. Several are not.

5

Reputation and deliverability

Some extensions cost you inbox placement.

6

The preloaded extensions

Where a certificate failure means total unavailability.

7

Defensive registration

What is worth holding and what is superstition.

8

Changing extension later

What it costs, and what you keep.

Chapter 1

What actually differs

Six things vary between extensions, and none of them are aesthetic.

What actually differs

This chapter is not written yet. Drop the prose into guide-bodies/<body>.html and rebuild.

Chapter 2

Eligibility and residency

The rules that can cost you a domain independently of renewal.

Eligibility and residency

This chapter is not written yet. Drop the prose into guide-bodies/<body>.html and rebuild.

Chapter 3

Price now versus price later

First-year discounts, premium renewals, and the gap.

Price now versus price later

This chapter is not written yet. Drop the prose into guide-bodies/<body>.html and rebuild.

Chapter 4

Recovery after expiry

Some registries are forgiving. Several are not.

Recovery after expiry

This chapter is not written yet. Drop the prose into guide-bodies/<body>.html and rebuild.

Chapter 5

Reputation and deliverability

Some extensions cost you inbox placement.

Reputation and deliverability

This chapter is not written yet. Drop the prose into guide-bodies/<body>.html and rebuild.

Chapter 6

The preloaded extensions

Where a certificate failure means total unavailability.

The preloaded extensions

This chapter is not written yet. Drop the prose into guide-bodies/<body>.html and rebuild.

Chapter 7

Defensive registration

What is worth holding and what is superstition.

Defensive registration

This chapter is not written yet. Drop the prose into guide-bodies/<body>.html and rebuild.

Chapter 8

Changing extension later

What it costs, and what you keep.

Changing extension later

This chapter is not written yet. Drop the prose into guide-bodies/<body>.html and rebuild.

Check yours

See where your own domain stands.

Everything in this guide, checked on your domain in about ten seconds. Free, no account, every finding shown in full.