The right TLD is not the "best" one in the abstract — it is the one whose story matches your project. For developers in 2026 there are six TLDs worth serious consideration, and choosing among them comes down to three things: audience perception, price, and technical restrictions. This guide compares them side by side.
The six TLDs we recommend for developers
namebox.dev generates names across exactly these six TLDs. They cover every realistic developer project: tools, apps, startups, CLIs, portfolios, and web3.
- .dev — Google's TLD for developers
- .app — Google's HTTPS-required TLD for apps
- .io — the default for tech startups
- .co — short alternative to .com
- .sh — niche for CLIs and shell tools
- .xyz — generic, popular for web3
Side-by-side comparison
- Price (renewal):
.xyz~$10 <.dev~$12 <.app~$14 <.co~$25 <.io~$40 <.sh~$60. - HSTS preload:
.devand.appare preloaded. Others are not. This forces HTTPS on browsers before they ever connect. - Geographic targeting: Google treats all six as generic. None will accidentally lock your site to a country.
- Credibility with engineers:
.dev>.sh>.io>.app>.co>.xyz. - Credibility with general business:
.co>.io>.app>.dev>.xyz>.sh.
If you are building a developer tool
Pick .dev. It signals "engineers built this for engineers" in three letters, is on the HSTS preload list, and is cheaper than .io. If your tool is a CLI, also consider .sh for the shell connotation, alone or paired with .dev.
If you are building a startup
.io remains the default for tech startups in 2026 — even with .ai hype, .io reads "we are a real software company" to investors and customers. If pricing is tight or the name you want is taken, .co is the closest fallback; just be aware it reads more business-general than engineer-specific.
If you are building an app
.app is the on-the-nose choice. It carries HSTS preload, so you must configure TLS before launch. Pair it with a .com for marketing pages and keep .app for the actual product.
If you are building a CLI or shell tool
.sh wins on semantics: yourtool.sh explains itself before anyone reads the tagline. Cost is high (~$60/year) so consider it the "premium" option; .dev is the realistic alternative.
If you are building a web3 or crypto project
.xyz is the convention in that community and avoids the overcrowding of .ai. Cost is low, registration is unrestricted, and the web3 audience reads it as neutral-to-positive.
What about .com?
.com is still the most credible TLD for general audiences and the easiest to remember for non-technical users. namebox.dev does not generate .com candidates because the meaningful namespace is exhausted: nearly every short English word and combination is parked or aftermarket. If you can buy your .com for a price you can justify, take it. Otherwise, the six TLDs above are realistic, available alternatives.
What about .ai?
.ai is genuinely useful for AI-native products, but at $60–$150/year with severe availability scarcity it is out of scope for an early-stage naming tool. We expect to add .ai support when the registration process stabilizes. For now, .io absorbs most of the use cases where .ai would be a stretch.
How to verify availability
Whatever TLD you pick, do not trust DNS-based "is it free?" tools. namebox.dev queries the authoritative registry for each TLD through RDAP (RFC 7483) — the modern replacement for WHOIS — and reports the actual registration status at the moment of your search. Run a search, see green names, and you can register at any accredited registrar immediately.
For the full process of evaluating a candidate name before you commit, see our guide on choosing a domain name.