SYSTEM OPERATIONAL: v2.4 RELEASED

Stop landing in
Spam Folders.

The infrastructure layer for high-velocity sales teams. We manage the IP rotation, DKIM signatures, and warm-up cycles so you can focus on the copy.

coldbox.app/campaigns/active

CAMPAIGN_V2_OUTREACH

RUNNING
AMAZON STRIPE SPOTIFY DISCORD FIGMA
AMAZON STRIPE SPOTIFY DISCORD FIGMA

The "Spray and Pray" era is over.
ESPs have evolved.

Google and Outlook now use AI-driven sentiment analysis and domain reputation scoring. If you send 100 emails from a new domain today, 98 of them will be burned by tomorrow.

"Coldbox abstracts the technical complexity. It's not just a sender; it's a reputation management engine."

Traditional

  • × Static IP Address
  • × Manual Warming

Coldbox

  • Rotational IPs
  • AI Warmup
[Image of global network map with server nodes]

/// GLOBAL INFRASTRUCTURE

Distributed Edge Sending

We route traffic through residential IPs near your target audience to maximize trust scores.

US-EAST
Load: 42%
EU-CENTRAL
Load: 65%
AP-SOUTH
Load: 21%
SA-EAST
Status: MAINTENANCE

Programmatic Outreach

Don't waste time clicking buttons. Integrate Coldbox directly into your SaaS or internal tools via our REST API.

Standardized JSON
Strictly typed request bodies.
Webhooks
Real-time events for opens, clicks, and replies.
curl_request.sh
curl -X POST https://api.coldbox.io/v1/campaigns \
  -H "Authorization: Bearer sk_live_51..." \
  -d '{
    "name": "Q4_Outreach",
    "config": {
      "daily_limit": 150,
      "auto_warm": true,
      "stop_on_reply": true
    },
    "audience": ["lead_8921", "lead_8922"]
  }'

Technical Comparison

FEATURE LEGACY ESPs COLDBOX
IP Rotation Shared Dirty Pool Dynamic Residential
Warm-up Network Synthetic (Fake) Peer-to-Peer (Real)
HTML Obfuscation None Polymorphic Injection
Limit Handling Hard Stop (429 Error) Auto-Failover Node

The Architecture

Built for scale, security, and deliverability.

Inbox Rotation Engine

Don't rely on one email address. Coldbox automatically distributes volume. If one account disconnects, the system reroutes traffic instantly.

> sending_batch_2491...
[email protected] [LIMIT REACHED]
>> REROUTING -> [email protected]
_

AI Spintax Generation

We rewrite email bodies automatically to ensure no two emails have the exact same hash signature.

Bounce Shield

Real-time SMTP verification before sending.

Unibox

Reply to leads from 50 different inboxes in one UI.

The Modern Data Stack

Salesforce
HubSpot
Slack
Supabase
AWS SES
Zapier

Enterprise Grade Security

We process millions of data points. Security is the foundation.

  • SOC2 Type II Certified
  • GDPR & CCPA Compliant
  • AES-256 Encryption at Rest
SOC2 Type II
GDPR Ready

Native Libraries

Node.js
npm install coldbox
Python
pip install coldbox-py
Go
go get github.com/coldbox

/// CASE STUDY: ACME INC

From 8% to 64% Open Rate in 21 Days

8%
Coldbox Integrated
64%

Changelog

NOV 14, 2025

Released v3.2.0

Added support for Outlook GraphQL API to bypass SMTP limits entirely.

OCT 02, 2025

Smart Warming Pools

Introduced industry-specific warming pools (B2B vs B2C).

Technical FAQ

Do you handle DMARC/DKIM?
Yes. We generate the CNAME records you need to add to your DNS provider.
What is the throughput limit?
We soft-cap accounts at 50/day initially, ramping to 150/day per inbox.

Transparent Capacity Pricing

Pay for the volume you send, not the seats you fill.

BOOTSTRAP
$49/mo

For solo founders validating an offer.

  • 5 Sender Accounts
  • 2,000 Emails / month
  • Basic Warmup
POPULAR
GROWTH
$129/mo

For sales teams scaling outreach.

  • Unlimited Sender Accounts
  • 25,000 Emails / month
  • AI Spintax Engine
  • Global Blocklist Monitor
AGENCY
$399/mo

White-label infrastructure.

  • Client Partitions
  • 150,000 Emails / month
  • Dedicated IP Address
  • API Access

Ready to ship?

Join 4,000+ engineers scaling their outreach on Coldbox.

Deploy your infrastructure.

SOC2 Compliant • GDPR Ready • 99.9% Uptime