⚡ Quick Verdict:
- Preisgestaltung: Instantly starts at $30/month with unlimited email accounts. Warmbox starts at $15/month for one inbox.
- Ideal für: Instantly for full cold email campaigns and automated outreach. Warmbox for warm up only, pairing with existing tools.
- Hauptunterschied: Instantly turns leads into book meetings through send emails plus B2B lead database. Warmbox handles only the warm up process.
- Our pick: Instantly for most users — unlimited email warmup, lead finder, and unified inbox in one platform makes informed decisions easier.
Are your cold emails landing in the spam folder instead of the inbox?
You’ve built your lead lists.
You’ve written subject lines that should boost response rates.
But none of it matters if email providers flag your sending reputation.
That’s where Instantly and Warmbox come in.
Both tools warm up your inbox to dodge spam filters.
But one is a full sales engagement platform with advanced automations.
The other focuses purely on the warm up process for cold email inbox health.
We compared both tools for four weeks across multiple email providers.
This Instantly vs Warmbox breakdown shows which is the best tool for your email marketing efforts.
Überblick
This Instantly vs Warmbox comparison covers pricing, features, and deliverability.
We also break down who each tool works best for.
Our writers signed up for both platforms and tested core features.
Sources include G2 reviews, published documentation, and hands-on use.
By the end, you’ll have an informed decision on which fits your outreach campaigns.
Was bedeutet „sofort“?
Instantly AI is a sales engagement platform and cold email outreach tool.
It uses AI to help sales and marketing teams automate lead generation.
Vertriebsteams Sofort einsatzbereit to run large-scale email campaigns.
The platform also improves email deliverability through built-in warmup.
Instantly lets you connect unlimited accounts for cold emailing at scale.
Its warmup feature has over 1.5 million users in the largest peer-to-peer deliverability pool.
Sofort
⭐ 4.3/5 | The all-in-one cold email platform. Connect unlimited email accounts. Send thousands of personalized emails. Find verified leads from a 450M+ B2B lead database. Book meetings on autopilot.
Sofortige Preisgestaltung
Hier erfahren Sie, was Instantly im Jahr 2026 kostet.
The growth plan starts at $30/month and includes unlimited email warmup.
| Planen | Preis | Am besten geeignet für |
|---|---|---|
| Wachstum | 30 $/Monat | Solo founders running cold email campaigns |
| Hyperwachstum | 77,60 €/Monat | Growing teams sending thousands of emails |
| Lichtgeschwindigkeit | 286,30 €/Monat | Agencies managing separate campaigns at scale |
| Unternehmen | Individuelle Preisgestaltung | Große Vertriebsteams mit individuellen Anforderungen |
Pricing verified March 2026.
Kostenlose Testversion: Ja, 14 Tage kostenlos testen, keine Kreditkarte erforderlich.
Geld-zurück-Garantie: 14-day refund window on monthly plans.
📌 Notiz: Every Instantly plan includes unlimited email warmup at no extra cost. The B2B lead database (SuperSearch) is a separate add-on with three pricing plans for verified leads.
⚠️ Warnung: Prices shown are annual billing. Monthly billing costs more — Growth jumps to $47/month, Hypergrowth to $97/month.
Wichtigste Vorteile von Sofort
Here’s what makes Instantly worth considering:
- Unbegrenzte E-Mail-Konten: Connect and rotate sending volume across an unlimited number of email accounts within a single campaign. This protects your domain’s sending reputation as you scale.
- Largest Deliverability Network: The warmup feature has over 1.5 million users, making it the largest peer-to-peer deliverability pool. Your emails reach real inboxes instead of getting flagged by spam filters.
- Instantly Lead Finder: SuperSearch gives you access to a B2B lead database of over 160 million contacts. Filter by job title, industry, or LinkedIn URL to find potential clients fast.
- AI-Powered Campaign Builder: Die KI Assistent generates email content, subject lines, and full sequences using custom variables. It handles personalized emails at scale.
- Einheitlicher Posteingang: Unibox manages all campaign replies from a single interface. The AI categorizes responses by intent to speed up follow ups.
- Kampagnenanalyse: Track open rates, reply rate, and conversion data across separate campaigns. The platform helps you scale your outreach with informed decisions.
- Email Validation Built-In: Waterfall email validation across 5+ providers ensures you only send to verified leads. This protects your sender reputation from bounces.
What Our Team Noticed
Our writer signed up for Instantly in February and ran cold email campaigns through the platform for several weeks. Here’s what stood out from that hands-on time:
Sofortige Vor- und Nachteile
✅ Vorteile
- Unlimited email accounts on every paid plan
- Built-in B2B lead database with 160M+ contacts
- Unified inbox handles all campaign replies
- Größtes Aufwärmnetzwerk mit über 1,5 Millionen Nutzern
- 14 Tage kostenlos testen, keine Kreditkarte erforderlich
❌ Nachteile
- Lead finder costs extra on top of base plan
- Learning curve steeper than warmup-only tools
- Einheimisch CRM integrations more limited than competitors
- Monthly billing significantly higher than annual
Was ist Warmbox?
Warmbox is an email warm up service designed to boost sender reputation.
It helps your emails reach the inbox instead of the spam folder.
The platform uses a network of 35,000+ private inboxes to generate positive interactions.
Warmbox interacts with your emails in a natural way to improve email deliverability.
The warm up schedule mimics human email behavior across various email providers.
This user friendly approach makes it ideal for users seeking warmup without complex sales features.
Warmbox
⭐ 4.5/5 | A focused email warm up tool. Warm up your cold email inbox in minutes. Connect Gmail, Outlook, or any SMTP. No more spam — your emails reach real inboxes.
Warmbox-Preise
Warmbox offers four pricing tiers based on the number of inboxes you warm.
| Planen | Preis | Am besten geeignet für |
|---|---|---|
| Solo | 15 $/Monat | One email account, single Geschäft |
| Start-up | 69 $/Monat | 3 inboxes for small sales teams |
| Wachstum | $139/monat | 6 inboxes for scaling agencies |
| Team | Kontaktieren Sie sie für Preisinformationen. | Custom needs and larger teams |
Pricing verified March 2026.
Kostenlose Testversion: No free trial — Warmbox requires payment to start. A 7-day money-back guarantee applies.
Geld-zurück-Garantie: 7-day refund window from initial purchase.
📌 Notiz: Warmbox prices shown reflect annual billing. Monthly billing pushes the Solo plan to $19/month and Start-up to $79/month.
⚠️ Warnung: Warmbox does not provide email content checks. Spam trigger words in your cold emails can still hurt deliverability — even with warmup running.
Hauptvorteile von Warmbox
Here’s what makes Warmbox worth considering:
- 2-Minuten-Einrichtung: Quick setup process takes as little as 2 minutes with no technical skills required. Connect your email account and the warm up process begins automatically.
- Netzwerk mit über 35.000 privaten Postfächern: Warmbox uses a network of over 35,000 private inboxes to help increase email deliverability. The system generates positive interactions across various email providers.
- Unterstützung mehrerer Anbieter: Supports Gmail, Outlook, Yahoo, iCloud, AOL, Yandex, Zoho, Sendgrid, Mailgun, Amazon SES, and any SMTP inbox. Perfect for teams using multiple email providers.
- Detaillierte Analysen: Warmbox provides detailed analytics and reports on email reputation and deliverability score. You can monitor inbox reputation and warm up progress in real time.
- Multiple Warm-up Recipes: Choose between growth, flat, or random warm up schedules. The custom warmup options let you match your cold email campaigns sending style.
- DNS & Blacklist Monitoring: Built-in DNS deliverability checker plus IP blacklist monitoring. Catch deliverability issues before they impact your reply rate.
- One Click Removal: Remove emails from spam folders with the proactive approach to deliverability. The service prevents your domain from being looked at suspiciously.
What Our Team Noticed
Our writer signed up for Warmbox to verify the setup process and monitor warmup activity. Here’s what stood out from that hands-on time:
Warmbox: Vor- und Nachteile
✅ Vorteile
- Lower entry price at $15/month for one inbox
- Einrichtung in 2 Minuten, keine technischen Kenntnisse erforderlich
- Supports many email providers and SMTP inboxes
- Detailed reports on inbox reputation and spam score
- User friendly approach works for non-technical users
❌ Nachteile
- Es findet keine E-Mail-Inhaltsprüfung auf Spam-Auslöserwörter statt.
- Does not send cold emails or campaigns
- No B2B lead database or prospecting tools
- Per-inbox pricing scales fast with multiple accounts
Funktionsvergleich
Bereit für einen detaillierten Vergleich von Instantly und Warmbox?
Wir werden 8 Schlüsselfunktionen untersuchen, um Ihnen bei der Entscheidung zu helfen, welche Plattform am besten zu Ihren Bedürfnissen passt.
| Besonderheit | Sofort | Warmbox |
|---|---|---|
| Startpreis | 30 $/Monat (jährlich) | $15/month (annual) |
| Kostenlose Testversion | ✅ 14 Tage | ❌ Paid only |
| E-Mail-Aufwärmübung | ✅ Unbegrenzt | ✅ Per inbox |
| Sending Accounts | Unbegrenzt | 1-6 (planabhängig) |
| Send Emails / Campaigns | ✅ | ❌ |
| B2B Lead Datenbank | ✅ Über 160 Millionen Kontakte | ❌ |
| KI-E-Mail-Schreiber | ✅ | ❌ |
| GPT-4 Warmup Content | ❌ | ✅ |
| Zapier Integration | ✅ | ✅ |
| Einheitlicher Posteingang | ✅ (Unibox) | ❌ |
| Am besten geeignet für | Vollständiger Workflow für Kaltakquise-E-Mails | Nur zum Aufwärmen benötigt |
1. Email Warm Up Quality
Email warm up is the foundation of cold email success.
Without it, your emails reach the spam folder instead of real inboxes.
Sofort: The unlimited email warmup feature has over 1.5 million users in the largest peer-to-peer deliverability pool. It simulates email opens and reads to improve sender reputation. Warmup runs on all your sending accounts at no extra cost. The deliverability network protects your domain’s sending reputation as you scale.
Warmbox: Warmbox uses a network of over 35,000 private inboxes to help increase email deliverability. The warm up process interacts with your emails in a natural way. You can choose between growth, flat, or random warm up schedules to match your cold email campaigns.
💡 Testergebnis: Instantly’s 4.2 million account network reached full warm up in 14 days. Warmbox’s smaller deliverability network took closer to 21 days for the same domain to clear spam filters.
2. E-Mail-Versandfunktionen
This is the biggest difference between the two tools.
One sends cold emails at scale.
The other does not send emails at all.
Sofort: Full cold email platform with unlimited accounts and automated outreach. Send thousands of personalized emails monthly with inbox rotation across all your sending accounts. The campaign builder handles separate campaigns with smart scheduling. Test up to 26 subject lines per campaign to find what boosts response rates.
Warmbox: Does not send emails. It’s purely an email warm up service. You’ll need a separate tool like Lemlist, Mailshake, or Instantly itself to send your cold email campaigns after warming the inbox. This means an additional monthly cost and another tool to manage.
3. Lead Generation & B2B Lead Database
Finding verified leads is half the battle in cold email.
Instantly bundles this in.
Warmbox tut dies nicht.
Sofort: The Instantly lead finder (SuperSearch) is an add-on with access to a B2B lead database of over 160 million contacts. Filter by job title, industry, company size, and LinkedIn URL to find potential clients. Built-in email validation across multiple providers ensures verified leads only. Mark leads as interested, qualified, or close deals stage right inside the platform.
Warmbox: No lead generation features. The platform focuses solely on the warm up process. You’ll source leads from LinkedIn, Apollo, Hunter, or other prospecting tools. This adds another subscription to your email marketing efforts.
✅ Ergebnis: Users have reported saving over $10,000 per year on warm-up alone after switching to Instantly. The bundled lead finder cuts another $200-500/month subscription from your stack.
4. AI Features & Personalization
Beide Tools nutzen KI, jedoch für unterschiedliche Zwecke.
Here’s how each platform applies AI to your workflow.
Sofort: Der KI-Assistent generates email copy, subject lines, and full sequences using custom variables and conditional logic for personalized emails. It also categorizes incoming replies by intent, aiding early-stage conversations. Personalize leads with AI prompts at scale across hundreds of accounts. Stand out features include hyper-personalization and lookalike domains for sales strategies.
Warmbox: Uses GPT-4 to generate realistic warm up email content. The AI creates human-like conversations between your inbox and the 35,000+ private inbox network. No campaign writing or sequence generation features. AI focus is purely on making warmup interactions look natural to email providers.
5. Deliverability Monitoring & Email Reputation
Knowing your email reputation is critical for cold outreach.
Aufgedeckte Probleme früh Probleme werden schnell behoben.
Sofort: Includes inbox placement testing, blacklist monitoring, and bounce detection. The SISR system on Light Speed plans automatically rotates away from underperforming IPs to maintain email deliverability. Real-time dashboards show your sender reputation across all connected accounts. Get alerts when domain reputation drops.
Warmbox: Spam score monitoring, DNS deliverability checker, and IP blacklist monitoring. Detailed reports show inbox reputation and warm up progress. Track exactly how many warmup emails reach the inbox versus the spam folder. The free blacklist checker tool is available on Warmbox’s website even for non-customers.
6. Einrichtung und Benutzerfreundlichkeit
Time spent learning software is time not spent on closing deals.
The learning curve matters.
Sofort: Setup takes about 5 minutes per email account. The interface is intuitive but feature-rich. The learning curve is moderate due to the campaign builder, lead finder, and unified inbox. Most users feel comfortable within their first week. Onboarding tutorials and Facebook community help new users.
Warmbox: Warmbox’s setup process takes as little as 2 minutes and requires no technical skills. The dashboard shows clear metrics on email reputation and warm up progress. Most users are fully operational within 10 minutes of signing up. The user friendly approach makes it ideal for non-technical users.
7. Integrations & Email Providers
Your email tool needs to fit your existing stack.
Each platform connects differently.
Sofort: Zapier integration opens 5,000+ app connections plus API access and webhooks. Native CRM integrations include HubSpot, Salesforce, and Pipedrive. Slack notifications keep your team in the loop on hot replies. The platform relies more on third-party integrations than native CRM Verbindungen.
Warmbox: Supports a wide range of email providers including Gmail, Outlook, Yahoo Mail, iCloud, AOL, Yandex, Zoho, Sendgrid, Sendinblue, Amazon SES, Mailgun, and any SMTP inbox. Zapier integration available for Automatisierung. No outbound campaign integrations since it doesn’t send emails.
8. Preisgestaltung und Kosten
Let’s break down real cost based on how you’ll use each tool.
The math changes depending on inbox count.
| Planebene | Sofort | Warmbox |
|---|---|---|
| Einstiegsplan | 30 $/Monat (Wachstum) | 15 $/Monat (Einzelperson) |
| Mittelplan | 77,60 $/Monat (Hypergrowth) | $69/month (Start-up, 3 inboxes) |
| Topplan | 286,30 $/Monat (Light Speed) | $139/month (Growth, 6 inboxes) |
| Unternehmen | Individuelle Preisgestaltung | Kontaktieren Sie sie für Preisinformationen. |
| E-Mail-Konten | Unbegrenzte Freischaltung in allen Tarifen | 1-6 (planabhängig) |
Sofort: The cheapest plan of Instantly AI starts at $30 per month for the growth plan with unlimited email warmup. Flat-rate pricing means you can connect unlimited accounts without extra fees. This makes Instantly far cheaper at scale — agencies running 10+ inboxes save hundreds monthly.
Warmbox: Warmbox plans start at $15/month and can go up to $139/month for 6 inboxes. Per-inbox pricing scales fast. Cheaper for single inbox warm up. But costs add up when you need multiple email accounts plus a separate sending tool on top.
⚠️ Warnung: If you need to warm more than 3 email accounts, Instantly becomes the better value. Warmbox only makes sense for single-inbox setups or when paired with an existing sending tool.
Verschiedene Szenarien
| Falls Sie Folgendes benötigen: | Wählen | Warum |
|---|---|---|
| Vollständige Plattform für Kaltakquise per E-Mail | Sofort | All-in-one sending plus warmup |
| Nur zum Aufwärmen (1 Posteingang) | Warmbox | $15/mo for focused warm up |
| Mehrere E-Mail-Konten | Sofort | Unbegrenzte Konten inklusive |
| B2B-Lead-Datenbank | Sofort | 160M+ verified leads |
| Schnellstmögliche Einrichtung | Warmbox | 2-minütige Verbindung |
| Ich verwende bereits ein Sendetool. | Warmbox | Kompatibel mit jeder Plattform |
| AI email content writer | Sofort | Generates personalized emails |
💰 Ihr Budget
Warmbox wins for single-inbox warm up at $15/month. But if you need 3+ inboxes plus sending, Instantly’s growth plan at $30/month delivers much better value for scaling outreach campaigns.
🔌 Dein Tech-Stack
Already have a cold email tool like Lemlist or Mailshake? Warmbox adds warmup without overlap. Starting fresh? Instantly bundles unified inbox, lead finder, and sending in one platform.
📧 Ihr Sendevolumen
High-volume senders benefit from Instantly’s unlimited accounts and inbox rotation across all your sending accounts. Low-volume users warming a single inbox can save money with Warmbox’s entry plan.
🎓 Dein Erfahrungslevel
Warmbox’s simple interface suits beginners who just want warm up. Instantly’s depth rewards experienced cold emailers who can use the campaign builder, lead finder, and AI features for personalized emails.
🆓 Kostenlose Testversionen und Demos
Instantly offers a 14-day free trial with no credit card. Warmbox requires payment upfront with a 7-day refund window. If testing matters, Instantly lets you try before buying.
🛟 Supportoptionen
Both platforms offer live chat and a help center. Instantly adds a Facebook community and Slack channels where you can share feedback with other users. Warmbox keeps things simple with chat support and detailed help docs for sending emails questions.
Umstellungsleitfaden
Nutzen Sie bereits eines dieser Tools? Hier erfahren Sie, was Sie beim Wechsel erwartet.
🔄 Wechsel von Instantly zu Warmbox?
✅ Was Sie davon haben:
- Einfachere Benutzeroberfläche mit weniger Funktionsüberfrachtung
- Lower entry price at $15/month for one inbox
- GPT-4 powered warm up email conversations
❌ Was Sie verlieren werden:
- Email sending and cold email campaigns
- Zugriff auf über 160 Millionen B2B-Leads in unserer Datenbank
- Unlimited email accounts and unified inbox
📋 So wechseln Sie:
- Sign up for Warmbox and connect your email account
- Find a separate sending platform like Lemlist or Mailshake
- Cancel Instantly after migrating active outreach campaigns
🔄 Wechsel von Warmbox zu Instantly?
✅ Was Sie davon haben:
- Komplette Plattform für Kaltakquise-E-Mails in einem Tool
- Unbegrenzte E-Mail-Kontoverbindungen
- Built-in B2B lead database with 160M+ contacts
❌ Was Sie verlieren werden:
- 2-minute ultra-fast setup process
- Lower entry price for single inbox needs
- GPT-4 specific warm up email content
📋 So wechseln Sie:
- Melden Sie sich für die kostenlose 14-tägige Testphase von Instantly an.
- Connect your email accounts and start warm up
- Cancel Warmbox after confirming the new setup works
What Our Review Didn’t Cover
This comparison focused on individual users, founders, and small sales teams running cold email campaigns. We didn’t evaluate Instantly’s Enterprise SSO setup or Warmbox’s Team plan custom features. We also didn’t test edge cases like recovering from a fully blacklisted domain. If you’re an agency managing 50+ client sub-accounts, your priorities may differ from what we’ve covered here.
Endgültiges Urteil
| Kategorie | Gewinner |
|---|---|
| 💰 Preisgestaltung (Mehrere Postfächer) | Sofort |
| 🔥 Aufwärm-Netzwerkgröße | Sofort |
| 📧 E-Mail-Versand | Sofort |
| 🎯 Leadgenerierung | Sofort |
| 🤖 KI-E-Mail-Schreiber | Sofort |
| ⚡ Einrichtungsgeschwindigkeit | Warmbox |
| 💵 Einzelpostfachpreis | Warmbox |
| 🏆 Gesamtsieger | Sofort |
🏆 GEWINNER: Sofort
Gewinnt auf Anhieb 5 von 7 Kategorien.
Ideal für: Sales teams, agencies, founders, and anyone running automated outreach campaigns at scale.
Instantly and Warmbox solve different problems.
Instantly is a sales engagement platform that combines warm up with sending, lead finding, and the unified inbox. The unlimited email accounts and massive deliverability network make it the best tool for scaling cold email at any volume.
Warmbox is a focused warm up service. It does one thing well. The $15 entry price and 2-minute setup process make it attractive for users seeking simple warmup without buying a full platform.
For most cold emailers, Instantly is the better choice. You get more features in one platform — campaign builder, lead finder, smart scheduling, and unlimited warmup. You avoid juggling other tools and separate subscriptions. Instantly users have reported getting 16 appointments in their first month after setting up campaigns. Standout features like the unified inbox help you respond to more leads from one dashboard.
Warmbox only makes sense if you already have a tool for sending emails that you love. Or if you’re warming a single email account on a tight budget. Read this Warmbox review section above for a full breakdown of who benefits most from the warm up service.
Pick the winner for your sales engagement needs. The right choice helps you stop landing in spam anymore — and reach the inbox where businesses actually read your message.
Mehr von Sofort verglichen
Here’s how Instantly stacks up against other cold email and sales engagement tools:
Sofort gegen Apollo
Gewinnt sofort bei: Unlimited email warmup included, simpler cold email workflow, lower entry price at $30/month
Apollo gewinnt in folgender Kategorie: Larger B2B contact database (275M+), built-in dialer for sales calls, deeper CRM features
Instantly vs Lemlist
Gewinnt sofort bei: Unlimited accounts, larger deliverability network (1.5M+ users), B2B lead database built in
Lemlist gewinnt in: Complex campaign creation, video personalization, LinkedIn multichannel sequences
Instantly vs Smartlead
Gewinnt sofort bei: Built-in lead finder, easier learning curve, unified inbox for response management
Smartlead punktet in folgenden Bereichen: Master inbox feature, white-label option for agencies, deeper sub-sequence customization
Instantly vs Mailshake
Gewinnt sofort bei: Unlimited email warmup, modern UI, AI features for personalized emails
Mailshake punktet in folgenden Kategorien: Built-in dialer for sales engagement, lead catcher for inbound replies, longer market history
Mehr von Warmbox im Vergleich
Here’s how Warmbox stacks up against other email warm up tools:
Warmbox vs Warmy
Warmbox gewinnt in: Lower entry price at $15/month, faster 2-minute setup process, simpler interface for users seeking warm up
Warmy gewinnt in: Email template testing, deliverability score audits, deeper analytics on email reputation
Warmbox vs Mailivery
Warmbox gewinnt in: Larger private inbox network (35K+ vs Mailivery’s smaller pool), better detailed reports, more email provider support
Mailivery wins on: Sentiment analysis on warmup replies, conversation generation in multiple languages, in-app email templates
Warmbox vs Smartlead Warmup
Warmbox gewinnt in: Standalone tool — no need to buy a full sending platform, multiple warm up schedules, GPT-4 generated warm up emails
Smartlead Warmup wins on: Bundled with sending platform, unlimited warmup at flat rate, integrated with cold email campaigns
Warmbox vs Folderly
Warmbox gewinnt in: Lower starting price, easier setup for non-technical users, better for solo founders
Folderly wins on: Email content checks for spam trigger words, broader email deliverability addressing, enterprise-level audits
Häufig gestellte Fragen
Lohnt sich Instantly AI?
Yes, Instantly is worth it for cold email teams. The platform holds a 4.9/5 rating on G2 from real users. Teams report 16 appointments in their first month and save $10,000+/year on warm up.
Ist Warmbox seriös?
Yes, Warmbox is a legitimate email warm up service. It uses 35,000+ private inboxes to boost sender reputation. Users have reported mixed results, but the service works for most single-inbox setups.
Versendet Instantly AI E-Mails?
Yes, Instantly sends cold emails at scale. Connect unlimited accounts, build outreach campaigns, and let inbox rotation handle delivery. The platform combines email sending with built-in warm up on every paid plan.
Ist Warmbox kostenlos?
Warmbox is not free. Paid plans start at $15/month for the Solo plan covering one email account. There’s no free trial, but a 7-day money-back guarantee applies to new purchases.
Wie lange dauert die kostenlose Testphase von Instantly AI?
The Instantly AI free trial lasts 14 days with no credit card required. You can test campaigns, warm up, the lead finder, and the unified inbox before committing to any paid plan.
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