How to Stay Safe and Secure Using Claude

When prompted, this image is how Claude AI sees itself: no face, no body.

A practical guide to protecting your account, your data, and your privacy when using Anthropic's Claude.

1. Lock down your account

• Use a unique, strong password. Don't reuse a password from another site.

• Check your security settings. Go to Settings in Claude.ai and review what authentication and device-management options are available to you — these have been expanding over time, so it's worth checking directly rather than assuming what's there.

• Verify your identity carefully. Anthropic has introduced identity verification (phone number or, in some cases, government ID) for account access. Use a phone number you control long-term, not a temporary/virtual one, since those have been flagged for issues. Anthropic states identity data is not used to train models and is used only to confirm who you are and meet legal/safety obligations (Claude Help Center, "Identity verification on Claude").

• Don't stay signed in on shared or public devices. If you're on a work or public network, avoid "stay signed in" options.

2. Understand how your data is used

This is the part most people skip — and it's the most important.

• Consumer plans (Free, Pro, Max) have a training toggle. Since an October 2025 policy update, Anthropic asks individual users whether they want conversations used to help improve future Claude models. This is opt-in, not automatic (Privacy Center, "How do I change my model improvement privacy settings?").

• Your choice changes how long your data is kept:

  • If you allow data use for model improvement: retention is up to 5 years.

  • If you don't allow it: retention is the standard 30 days (Anthropic, "Data policies").

• Deleted conversations are not used for training, regardless of your setting.

• Flagged content is the exception. If a conversation is flagged by Anthropic's trust-and-safety systems as a possible policy violation, it can be retained longer (up to 2 years for the content, up to 7 years for classification scores) even if you opted out of training.

• Business and enterprise plans are different. Claude for Work, Claude for Education, Claude Gov, and API use (including through AWS Bedrock and Google Cloud) are not used for training by default and follow separate, generally stricter data-handling terms.

• Where to check/change this: claude.ai → Settings → Privacy (sometimes shown as data-privacy-controls).

Action item: Open your privacy settings today and confirm the toggle actually reflects what you want — don't assume.

3. Know what not to share

Even with good account security, some information shouldn't go into any chatbot:

• Passwords, API keys, private keys, or authentication tokens

• Full financial account numbers, Social Security/national ID numbers

• Confidential business data you're not authorized to share externally

• Medical records or other sensitive personal data tied to identifiable people (yours or others')

• Anything covered by an NDA or client confidentiality agreement

If you're pasting logs, code, or documents to get help, scrub identifiers and secrets first.

4. Treat Claude's output like a draft, not a verdict

• Claude can make mistakes, especially with fast-changing facts, numbers, citations, or niche technical details. Verify anything important — medical, legal, financial, or safety-related — with a qualified source before acting on it.

• Be cautious with links or instructions Claude gives you that involve installing software, running scripts, or entering credentials — read before you execute.

5. Watch for prompt injection and social engineering

If you use Claude with connected tools (browsing, file access, integrations), be aware of "prompt injection" — where malicious instructions hidden in a webpage, document, or email try to manipulate the AI's behavior. Good habits:

• Don't grant more tool access/permissions than a task needs.

• Review what an agent is about to do before approving actions that send messages, make purchases, or modify files on your behalf.

• Be skeptical of any content (including AI output) urging you to bypass normal verification steps.

6. Account and data cleanup

• Delete conversations you no longer need. This starts the removal process from Anthropic's backend (standard case: gone from backend within about 30 days).

• Deleting your account: Free users can delete directly in Settings → Account. Paid users need to cancel the subscription first, let the billing period end, then delete the account. Deletion is permanent — you lose access to saved chats (Claude Privacy Settings guidance, consistent with Anthropic's account deletion flow).

7. For businesses: extra controls worth knowing about

If you're deploying Claude at work, Anthropic's enterprise offerings include:

• AES-256 encryption at rest and TLS 1.2+ in transit

• Multi-factor authentication required internally for staff systems holding customer data

• SOC 2 certification and third-party audits (Trust Center)

• Admin controls like Tenant Restrictions (network-level access control) and Compliance API integrations for monitoring sensitive data exposure in prompts/files

Quick checklist

• Strong, unique password + review available security settings

• Confirm your training/data-use toggle matches your preference

• Never paste secrets, credentials, or sensitive personal data

• Verify important factual output independently

• Review permissions before letting Claude take actions on your behalf

• Periodically delete old conversations you don't need

Sources

• Anthropic, Claude Help Center — "Identity verification on Claude" (support.claude.com)

• Anthropic Privacy Center — "How do I change my model improvement privacy settings?" (privacy.claude.com)

• Anthropic — "Data policies" for Claude Code / consumer and commercial plans (docs.anthropic.com)

• Anthropic, Claude Help Center — "Data retention practices for Covered Models" (support.claude.com)

• Anthropic, Claude Help Center — "Claude for Teachers: your data and our terms" (encryption, MFA, SOC 2 details) (support.claude.com)

• Anthropic, Claude Help Center — "Enforce network-level access control with Tenant Restrictions" (support.claude.com)

This guide reflects publicly available Anthropic documentation as of July 2026. Settings and policies change — always check claude.ai/settings and Anthropic's official Privacy Center for the current state.