Send at scale.
Land in the inbox.
Coldscale rotates your sending across a pool of warmed mailboxes, throttles daily volume automatically, and keeps deliverability agencies and sales ops teams actually trust.
Everything Instantly built — plus deliverability you can actually audit.
Coldscale is the cold-email stack sales ops teams move to after their third deliverability incident. Six pieces, tightly integrated.
Smart account rotation
Distribute your campaign evenly across every connected mailbox. Coldscale respects per-account daily caps and skips any account with a dip in reputation.
60-day warm-up on autopilot
Coldscale ramps a fresh mailbox from 5 sends/day to 30 sends/day over eight weeks — conversational replies, seed lists, and SPF/DKIM verification built in.
Deliverability that matches Postmaster
Per-account reputation score, inbox vs spam placement, and blacklist monitoring — the exact signals Google and Microsoft use, surfaced before you burn a domain.
AES-256 SMTP credential vault
Connect Gmail, Google Workspace or custom SMTP. Credentials are encrypted at rest with AES-256-GCM and rotated with your 32-char master key.
CSV leads + liquid variables
Drop a CSV with firstName, company, custom_1..n. Coldscale detects columns, builds {{variable}} chips, and flags missing fields before launch.
Claude-powered copy variations
Describe your offer + ICP. Coldscale returns three subject/body pairs optimized for reply rate — then you launch directly into a campaign.
The 60-day ramp that keeps Gmail happy.
Every new mailbox spends eight weeks in our warm-up pool — exchanging conversational replies with ~900 other verified accounts before it touches a single cold lead.
Connect your mailboxes
Add Google Workspace or custom SMTP accounts. We encrypt the credentials and start the 60-day warm-up schedule immediately.
Upload leads + write the email
Paste your ICP into the AI writer or craft it yourself. Upload a CSV, pick which mailboxes to rotate across, set a daily cap.
Launch and watch inbox rate
Coldscale throttles sends across your pool, tracks opens and replies, and pauses any mailbox whose reputation slips below 70.
3,800+ mailboxes warmed. Zero Gmail suspensions this quarter.
Agencies and in-house sales ops teams who switched to Coldscale after getting burned somewhere else.
“We moved 9 agency sending accounts onto Coldscale rotation. Inbox placement went from 61% on our old stack to 93% in six weeks — and our SDRs stopped babysitting warm-up spreadsheets.”
“Running 22 mailboxes across four domains for our clients. The smart rotation kept every account under its safe daily cap — zero Google suspensions across Q1 and 14,200 booked demos.”
“The deliverability dashboard is the first one I've seen that matches what Google Postmaster actually reports. Saved us from nuking a 3-year-old domain on a bad send.”
Flat rates. No per-send surcharges. Ever.
Pick a tier based on how many mailboxes you're running — Coldscale never charges per email or per lead.
Starter
For solo operators running a single domain.
- Up to 3 sending accounts
- 60-day automated warm-up
- 2,500 sends / month
- Deliverability dashboard
- AI email writer (Claude)
Growth
For sales teams scaling multi-mailbox outbound.
- Up to 10 sending accounts
- Smart rotation across domains
- 25,000 sends / month
- Blacklist + reputation alerts
- Custom SMTP + Workspace OAuth
- Priority support
Agency
For agencies managing client outbound at volume.
- Unlimited sending accounts
- White-label client workspaces
- Unlimited monthly sends
- Dedicated IP pool option
- API + webhook access
- SSO + SOC2 report