SMTP + API
OTP and magic links, one integration
Give every client or application its own credential, limits and security events while delivering through a consistent sender identity.
Passwordless authentication delivery
One Sender.
Forget passwords.
Deliver one-time codes and magic links through one trusted SMTP and API layer—fast for real users, rate-limited against attackers, and built on infrastructure you control.
OTP + magic linksSingle-use codesIdentity + IP throttling
sign-in requestYour app
senderSenderMesh
destinationInbox
OTP senta•••@company.com
Link sentr•••@business.co.uk
01 / Platform
The secure delivery layer between sign-in and the inbox.
Help clients remove passwords without creating a new abuse channel. Every authentication request is traceable, throttled and short-lived.
SPF passDKIM passDMARC aligned
Authentication built in
A coherent sender, signing domain and SMTP identity—without a confusing “via” label.
Controlled network
Abuse resistance by default
SenderMesh accepts authentication traffic from reviewed clients and slows enumeration, resend floods and bot-driven inbox bombing.
- Generic responses prevent account discovery
- Old codes invalidated on resend
- Bounce and complaint suppression
02 / Security + reputation guardrails
Fast for users. Expensive for attackers.
Tenant volume, API speed and end-user attempts are limited separately, keeping valid sign-in quick without enabling inbox floods.
auth emails / day
- 1 API request / second
- Burst up to 5 requests
- Authentication traffic only
auth emails / day
- 5 API requests / second
- Burst up to 20 requests
- Automatic queue protection
evidence-based volume
- Higher sustained API rate
- Dedicated sending stream
- Reputation review
IMPORTANT: SMTP dispatch remains subject to IP warm-up and mailbox-provider feedback. Excess is queued, not dropped.
Start near 20 authentication requests per IP or device per hour, then challenge or temporarily block suspicious bursts. Return the same public response whether an account exists.
Assurance note: Email OTP and magic links reduce password reuse and credential stuffing, but they are not phishing-resistant. For sensitive accounts or transactions, offer passkeys, security keys or an additional independent factor.
03 / Deliverability
Wanted sign-in mail reaches more inboxes.
Authentication alignment, predictable user-triggered volume, clean recipients, immediate suppression and strict tenant review protect the domain and IP from looking like spam.
Domain healthHealthy
92 / 100
AUTHENTICATIONAlignedBOUNCES0.4%COMPLAINTS0.02%QUEUENormal
04 / Brand system
Confident on the site. Calm in the inbox.
The platform uses near-black and energetic emerald. OTP emails use white, charcoal and a deeper accessible green so security messages feel clear and trustworthy.
SenderMesh
SECURE SIGN-IN
SECURE SIGN-IN
Your code is 483 921
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Continue securelyPrivate beta
Replace passwords.
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