Stealth Bulk Mailer — Windows Desktop

Email at
scale.
Land in
inbox.

High-volume campaigns without the spam folder. 9Sender runs entirely on your machine — no SaaS, no subscription, no telemetry. Just results.

Download for Windows See features
Local-first No telemetry Windows 10 / 11
01 / Capabilities

Everything a serious sender needs.

01

Stealth Engine

Zero-width characters, Unicode homoglyphs, and randomized message headers defeat spam classifiers at the byte level — without altering message intent.

02

AI Content Generation

Connects to GPT, Claude, or any OpenAI-compatible endpoint. Generates subjects, rewrites body copy, auto-optimizes to non-openers.

03

SMTP Rotation

Round-robin, weighted, or per-domain routing across unlimited accounts. Exponential backoff retry on failures.

04

Open & Bounce Tracking

Pixel tracking with A/B test attribution, hard/soft bounce classification, and automatic suppression list sync. Up to 50,000 events per local file.

05

Scheduler

Cron-based delivery windows with timezone awareness and SMTP warm-up ramp plans.

06

Local-First, Always

All data in JSON files on your disk. No cloud database, no SaaS, no outbound traffic except the SMTP and AI endpoints you configure yourself.

02 / By the numbers
50k
tracking events per local file
∞
SMTP accounts supported
3+
AI providers — GPT, Claude, custom
0
external runtime dependencies
03 / Download

Windows Desktop App.

Electron-based, fully portable. Runs offline. No installer dependencies. Windows 10 or later, x64 only.

Windows 10 / 11 x64 — Portable EXE Electron No installer required
Download 9Sender.exe

v1.0.0 — one-time purchase — Windows only