Mailwarm
A tool that quietly builds up trust with email providers like Gmail and Outlook before you start sending real campaigns, so your messages land in the inbox instead of the spam folder.
🔗 Visit Mailwarm
Description
A brand-new email address, or one that suddenly starts sending a lot of messages, looks suspicious to Gmail, Outlook and other providers — even if every email is legitimate. That's why cold outreach or a fresh marketing account often ends up in spam no matter how good the message is: the sender simply hasn't earned trust yet. Mailwarm automates the process of earning that trust by having your account send and receive email with a large network of real, aged inboxes, generating the kind of positive engagement signals (opens, replies, moving mail out of spam) that providers look for.
Mailwarm connects to your email account — Gmail, Outlook, Yahoo, Zoho, or generic SMTP — and runs automated warm-up activity against a network of 50,000+ real, aged inboxes around the clock, while a live dashboard tracks whether your warm-up emails are landing in the inbox or spam in real time. It's Y Combinator-backed and reports being trusted by over 10,000 teams, including recognizable names like Michelin, Microsoft and Deel, with claimed results of 98% open rates and 59% reply rates during warm-up. There's no traditional free trial — warm-up begins immediately once you connect an account — and pricing runs on a subscription plus $0.02 per additional interaction beyond the plan's included volume, with custom enterprise plans available.
💬 Our review
The short version: if you're about to run outbound email at any real volume — sales outreach, a new marketing domain, a fresh account after a provider flag — skipping warm-up is one of the more common and avoidable ways campaigns quietly fail before anyone reads a single message.
Mailwarm's core mechanic (simulated positive engagement across a large real-inbox network) is the standard, proven approach to reputation building, and Y Combinator backing plus named enterprise customers like Microsoft are a reasonable trust signal in a space that has its share of shady "inbox farm" tools. The claimed 98% open / 59% reply rates are Mailwarm's own warm-up statistics, not a promise about your actual campaign performance — treat them as evidence the mechanism works, not a guarantee of your results. Competitively, Mailwarm sits in a crowded field (Lemwarm, Warmup Inbox, and built-in warm-up features inside tools like Instantly or Smartlead), so the real question is whether you need a dedicated best-of-breed warm-up tool or whether an all-in-one outreach platform's built-in warm-up is good enough — for teams sending at real scale from multiple domains, a dedicated tool like Mailwarm usually does a more thorough job.
💰 Pricing
📊 Global score
🤖 AI-enriched data
Abonnement de base + $0,02 par interaction au-delà du volume inclus ; pas d'essai gratuit classique, le warm-up démarre dès la connexion du compte
Pros
Réseau de 50 000+ boîtes réelles et anciennes pour un warm-up crédible
Tableau de bord en temps réel du placement inbox vs spam
Compatible Gmail, Outlook, Yahoo, Zoho, SMTP générique
Soutenu par Y Combinator, clients référencés (Michelin, Microsoft, Deel)
Cons
Marché concurrentiel avec plusieurs alternatives établies
Statistiques 98%/59% mesurent le warm-up, pas la performance de vos propres campagnes
Pas d'essai gratuit classique avant engagement
Coût par interaction à surveiller au-delà du volume inclus