How to get a Claude AI verification number
The process takes under two minutes. Open ASMS.ai and browse the list of available numbers. Each entry shows the country flag, the number in international format, and how recently it received a message, picking one that has been active recently gives you the best chance of a fast delivery. Copy the number.
Go to Claude.ai or the Anthropic sign-up page and paste the number into the phone field. Anthropic will dispatch an Anthropic verification SMS with a 6-digit code to that line. Switch back to ASMS.ai, open the number's message page, and the code will be waiting. Enter it on Claude's page and the account is verified. The entire sequence, choosing a number, triggering the SMS, reading the code, typically completes in well under a minute.
There is no app to install, no account to create on ASMS.ai, and nothing to clean up afterwards. Messages on public numbers are wiped periodically, so old codes do not accumulate.
Is it really free?
Yes, completely. The public shared numbers on ASMS.ai cost nothing to use. There is no freemium paywall hiding the actual verification step, no trial period that asks for a card, and no hidden charge after the SMS arrives. The free tier is the product.
The service is funded by its premium tier: private numbers (where only you see the messages) and a developer API with full REST endpoints and a native MCP server for AI agents. If you need that, it is there. If you just want a Claude AI phone number for a one-time sign-up, the free shared numbers handle it without any account or payment.
Privacy and security, what 'shared' actually means
Shared numbers are public by design. Anyone who visits the number's page on ASMS.ai can read the messages sent to it. For a disposable verification code this is perfectly acceptable: the code is useless the moment it has been entered, and your Claude account is then protected by your password and any additional security you add.
Where you should be careful is any SMS that carries genuinely sensitive content, a password-reset link, a bank's two-factor code, or anything where the message itself has value beyond a single use. For Claude AI sign-up verification, a shared number is entirely appropriate. The code arrives, you use it, and it expires.
If you need incoming messages to stay private, because you are running automated tests or managing multiple accounts, ASMS.ai's paid private numbers keep all messages visible only to you. That is the right tool for ongoing or sensitive workflows, not a one-off Claude verification.
Why people use a temporary number for Claude
The most common reason is simple: most people would rather not attach their personal mobile number to every platform they sign up for. Phone numbers are persistent identifiers that services can use to link you across products, sell to data brokers, or target with unsolicited marketing. A temporary claude verification number keeps that link clean.
Account separation is another frequent use case. Developers and researchers who work with Claude's API often maintain more than one Anthropic account, a personal one and a client or team account, and a free temporary number makes that practical without sourcing a second SIM or a second device.
A smaller but real group of users are in regions where Anthropic's SMS delivery to local carriers is slow. Choosing a US or UK number on ASMS.ai, where network infrastructure is reliable, often gets the code through faster than a local number would.
Which services can you verify with ASMS.ai?
Claude AI and Anthropic accounts are among the most frequently verified services on ASMS.ai, but the numbers work with any platform that sends a standard SMS verification code: OpenAI, Google, Microsoft, WhatsApp, Telegram, Discord, Twitter/X, Facebook, Instagram, TikTok, Uber, and hundreds of other apps and websites.
The numbers are real SIM-based lines, not VoIP, which means they pass the carrier checks that many services apply when validating a phone number. Because fresh numbers are added to ASMS.ai daily, there is usually a line available that has not been flagged or exhausted by earlier verifications. If one number does not receive the code within 60 seconds, switch to another, it takes only seconds.
Countries and number availability
ASMS.ai currently provides numbers from the United States, United Kingdom, Germany, Georgia, and Ukraine, with additional regions added as the service grows. Country selection matters for Claude specifically because Anthropic operates across all of those countries, so the verification SMS will be sent without issue regardless of which you choose.
Within each country there are typically several numbers active at any given time. The list on the site shows recent message activity so you can skip lines that appear dormant. Numbers that stop receiving messages reliably are rotated out and replaced, keeping the pool current.
For most users, a US number is the practical default: they are the most consistently stocked and tend to get the fastest delivery from Anthropic's SMS provider. UK numbers are a reliable second choice. If your workflow requires a specific country, check availability before starting the Claude sign-up flow.
AnonymSMS and ASMS.ai, same service, new name
The service launched in 2018 under the name AnonymSMS and built a large, loyal user base across Europe and North America. In 2026 it rebranded to ASMS.ai and relaunched with a cleaner interface, expanded country coverage, and a dedicated developer API tier.
If you reached this page after searching for AnonymSMS, you are exactly where you need to be. The core free offering is unchanged: public shared numbers, no registration, messages displayed instantly, periodic wipe. The new name brought improved infrastructure and new features, not new restrictions.
For developers: API and MCP server
If you are building anything that needs to automate SMS reception, a CI testing harness, an AI agent onboarding flow, or a tool that verifies multiple accounts programmatically, ASMS.ai offers a REST API and a native MCP server. The MCP interface lets AI agents, including Claude running via Anthropic's API, call SMS-receive actions as structured tool calls with no custom integration work needed on your side.
The API tier includes private numbers, full message history, webhook delivery, and rate limits suited to production workloads. It is a natural fit for engineering teams already working with Anthropic's platform who need to fold SMS verification into automated pipelines. Pricing and documentation are on the API page.