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21.app
is for sale
Secure Transactions Secure Transactions
Fast Domain Transfers Fast Domain Transfers
Flexible Payments Flexible Payments

About 21.app

21.app is a sleek, memorable domain that captures the essence of innovation and forward-thinking. Its brevity—just two characters—ensures instant recognition and easy recall, perfect for the fast-paced digital landscape. Picture a platform for financial tracking, a next-gen health app, or a vibrant social network. The number 21 resonates with youthful energy and new beginnings, evoking images of reaching milestones and celebrating achievements. This domain is not just a name; it's a powerful brandable asset that promises to elevate any startup, making it an irresistible opportunity for visionary entrepreneurs ready to make their mark.

Does 21.app fit your brand?

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Buy with Confidence

  • Ownership verified
  • Payment protected until transfer is complete
  • Fast, guided transfer

Purchase Protection Program

100% refund guaranteed if domain can't be transferred. Learn more

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Great domains rarely drop in price. Get notified of any changes to 21.app.

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Step-by-Step Purchase Guide

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Why Buy With Atom?

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Customers

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Inc. 5000

Fastest-Growing Companies in the US

2025

Trailblazer Award

Honored by the Internet Commerce Association

Frequently Asked Questions

After payment is completed for 21.app, we’ll guide you through the best available transfer option based on the domain’s current registrar and extension.

For most domains, we’ll seamlessly move the domain to your Atom account. If the domain extension is not yet supported or there is an exception, we can typically assist with either a registrar account push or by providing an authorization (auth) code so you can transfer the domain to your preferred registrar.

21.app and other names on Atom Marketplace do not include Trademarks or business registration. This is because Trademarks are unique to the industry (class) as well as country of the business. Since 21.app can be purchased by anyone for any use, it would not be possible for us to file a Trademark in advance.

We recommend that you do some research and/or seek legal advice to ensure that the name you are interested in does not have a direct Trademark conflict by a competitor in your industry and within your region. If there is no direct conflict, or the existing trademark is unrelated to how you plan to use it, then you have a good chance of being able to trademark the name yourself. If there is an existing trademark, keep in mind that, as long as your business is in a different industry, you may still be able to file a trademark for the name.

We also offer a Trademark validation & Filing service which includes upfront Trademark validation and filing the Trademark application on your behalf by a licensed Trademark Attorney.

Domains purchased on our platform are generally non-refundable. Because domain transfers are typically instant or near-instant, refunds cannot be issued once a domain transfer has been initiated or completed.

If a domain has not yet been transferred, a refund may be considered only if all of the following conditions are met:

  • The refund request is made on the same day as the purchase
  • The domain transfer has not been initiated (including registrar push or transfer-out)
  • The domain was purchased with a one-time payment (not installments)

If a refund is approved under these conditions, it may be subject to a cancellation fee to cover payment processing costs.

The purchase price of a domain on our marketplace is a one-time payment. Once the domain is transferred to your account, you will own it.

To keep the domain active, you’ll need to renew it each year through your domain registrar. Renewal fees vary by registrar and domain extension. For example, .com domains typically renew for around $10–$20 per year, while other extensions such as .io, .xyz, or .ai may cost more.

To avoid accidental expiration, we recommend keeping a valid credit card on file with your registrar and enabling auto-renewal so your domain renews automatically each year.

All domain purchases are backed by our Purchase Protection Guarantee. With over 100,000 customers worldwide, Atom has been featured in the Inc 5000 list of fastest growing companies for 4 consecutive years.

We initiate most domain transfers within 1 Business day of purchase. If, for any reason, we are unable to transfer the domain to your ownership, we offer a 100% refund.

Some domains on our marketplace offer Lease to Own plans, allowing you to purchase a domain through smaller monthly payments instead of paying the full amount upfront.

You can begin using the domain after your first payment. The domain will remain securely held with Atom until all payments are completed, and our team can assist with any domain setting changes while the Lease to Own plan is active.

Once the Lease to Own plan has been paid in full, the domain will be transferred to your ownership.

If your plans change, you can cancel the Lease to Own plan at any time. Learn more about how Lease to Own plans work in our detailed guide: How Lease to Own Works.

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$48,888

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