.io vs .dev: two devtools TLDs

Side-by-side comparison

Both are generic gTLDs treated identically by search and email systems. The split is recognition and pricing.

Inventory is the practical difference

.io's good one-word names are mostly held — and held by people who know what they're worth. .dev still has unregistered premium one-word names available at registry pricing or low five-figure aftermarket. For founders short on budget, .dev gives more raw choice today.

Decision framework

Pick .io if you want immediate developer credibility, you can afford premium .io aftermarket, and the exact name you want is in the .io aftermarket. Pick .dev if budget is tight, you want a clean unregistered premium name, and you can live with a slightly less saturated TLD.

Frequently asked questions

Is .io or .dev better for a developer tool in 2026?

.io for infrastructure, platforms, APIs, and serious technical products (Sentry, Linear, Render, Socket all launched on .io). .dev for SDKs, CLIs, documentation surfaces, and tools whose users are developers in their day-job role. Many brands hold both.

Which is cheaper, .io or .dev?

.dev at the registry (~$15–25/yr) versus .io (~$30–60/yr). On the aftermarket, premium .io is deeper and trades higher because the TLD is older and more held. Premium one-word .dev is available at lower price points than equivalent .io.

Does .dev have mandatory HTTPS?

Yes. .dev requires HSTS via the Chromium HSTS preload list — every .dev domain is HTTPS-only at the browser level. .io does not have this requirement, but every credible .io site is HTTPS in 2026 regardless.

Is .io or .dev better for SEO?

Neither carries an inherent advantage. Both are generic gTLDs to Google with no geo-targeting penalty. SEO outcomes depend on content depth, backlinks, Core Web Vitals, and user signals — not the TLD.

Which TLD do developers prefer to type?

Equally. Both are well-known in technical circles. .io has slightly more brand recognition because it's older and held by more category-defining brands. .dev is more literal and self-explanatory ('this is for developers').

Which TLD do investors prefer?

Seed-stage technical investors are equally comfortable with .io and .dev. Growth-stage and generalist investors lean toward .com regardless of category. Neither .io nor .dev blocks a round, but acquirers at exit typically expect the matching .com to be acquired.

Can I run email on .io or .dev?

Yes, both. Full DNS support (MX, SPF, DKIM, DMARC, BIMI, DNSSEC). Deliverability is identical to .com when configured correctly. The .dev HSTS preload affects HTTP only, not SMTP.

Should I own both .io and .dev?

If budget permits, yes. Defensive registration of the alternate is under $100/yr combined. Pick one as primary and 301-redirect the other. Many companies hold both and use .dev for docs or developer-focused subdomains.

Is .io safer long-term than .dev?

.io is a ccTLD (British Indian Ocean Territory) with some long-term governance uncertainty; ICANN and the registry have committed to namespace continuity. .dev is a generic TLD operated by Google Registry with no equivalent ccTLD risk. .dev edges out on pure governance stability.

Will .io be retired?

No near-term retirement risk. .io transitioned from Internet Computer Bureau to Identity Digital and remains widely held by major tech brands. ICANN and the registry have stated they will preserve the namespace if the territory's status changes.

How do I buy a premium .io or .dev not listed for sale?

Most premium one-word .io and .dev names trade off-market via brokers. Direct founder outreach typically inflates ask prices 2–5× versus anonymous broker outreach. Use a specialist broker for comp-anchored valuation and escrowed transfer.

Will .io or .dev pricing stay stable?

.io has had modest renewal increases over the last decade and now sits at $30–60/yr. .dev has been stable under Google Registry operation. Plan for predictable renewals on both over a 5-year horizon.

Is .dev better than .io for AI-developer tooling?

Slightly, if the primary audience is developers building with AI (eval harnesses, prompt tooling, SDKs). .io reads as 'AI infrastructure for platforms' (vector DBs, MLOps). The split is subtle — pick by who's typing it in and what stage of the AI stack you sit at.