Yes, Hunter.io is legal. It collects email addresses only from publicly available sources and is GDPR-compliant with built-in data protection measures.

How to Use Hunter IO for Easy Lead Generation in 2026?

Q: How to check if an email is legit?

Use Hunter.io's Email Verifier. Enter the address and Hunter.io returns a status of Valid, Risky, or Invalid based on real-time mail server checks.

Q: How does Hunter.io find emails?

Hunter.io finds emails by crawling publicly available web pages, professional directories, and published documents. It also detects email format patterns at each company to generate likely addresses for contacts not directly indexed.

by Fahim Joharder | Last updated Mar 5, 2026

Quick Start

This guide covers every Hunter.io feature:

Getting Started — Create account and basic setup
How to Use Domain Search — Find all email addresses tied to any company domain
How to Use Email Finder — Get a verified email for any specific contact
How to Use Email Verifier — Confirm addresses are valid before sending
How to Use Campaigns — Send personalized cold email sequences at scale
How to Use Google Sheets Add-on — Run email lookups inside your spreadsheets
How to Use Browser Extension — Find emails while browsing any website
How to Use Bulk Tasks — Search and verify thousands of emails at once
How to Use API Key — Connect Hunter.io data to your own tools
How to Use AI Writing Assistant — Draft better cold emails faster with AI

Time needed: 5 minutes per feature

Also in this guide: Pro Tips | Common Mistakes | Troubleshooting | Pricing | Alternatives

Why Trust This Guide

I’ve tested every Hunter.io feature hands-on to write this guide.

This how to use Hunter IO tutorial comes from real experience — not vendor marketing.

Hunter.io is one of the most trusted email finding and outreach tools available today.

But most users only scratch the surface of what it can do.

This guide shows you how to use every major feature.

Step by step, with screenshots and pro tips.

Hunter.io Tutorial

This complete Hunter.io tutorial walks you through every feature step by step, from initial setup to advanced outreach tips.

Hunter.io

Find and verify professional email addresses in seconds. Hunter.io lets you reach the right people at any company with 95%+ accuracy. Start free — no credit card required.

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HUNTER.IO ALTERNATIVES →

Getting Started with Hunter.io

Before using any feature, complete this one-time setup.

It takes about 3 minutes.

Watch this quick overview first:

Now let’s walk through each step.

Step 1: Create Your Account

Go to hunter.io and click “Sign Up Free.”

Enter your email address and create a password.

Confirm your email to activate the account.

✓ Checkpoint: Check your inbox for a confirmation email from Hunter.io.

Step 2: Access the Dashboard

Hunter.io is fully web-based — no download required.

Here’s what the dashboard looks like:

✓ Checkpoint: You should see the main navigation with Domain Search, Email Finder, and Campaigns.

Step 3: Complete Initial Setup

Connect your email account under Settings > Email Accounts.

This unlocks the Campaigns feature for outreach.

Install the Chrome extension for on-the-go email finding.

✅ Done: You’re ready to use any Hunter.io feature below.

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How to Use Hunter.io Domain Search

Domain Search lets you find all publicly listed email addresses associated with any company’s website.

Here’s how to use it step by step.

Watch Domain Search in action:

Now let’s break down each step.

Step 1: Enter the Target Domain

Click “Domain Search” in the left navigation menu.

Type the company’s domain name into the search bar.

Press Enter or click the search button.

Step 2: Review the Results

Hunter.io returns a list of email addresses found for that domain.

Each result shows the name, job title, and confidence score.

Here’s what this looks like:

✓ Checkpoint: You should see a list of contacts with their department, role, and email format pattern.

Step 3: Save Contacts as Leads

Click the save icon next to any contact to add them to your Leads list.

You can filter results by department to find the right person faster.

Export the full list to CSV for use in other tools.

✅ Result: You now have a curated list of contacts at any target company ready for outreach.

💡 Pro Tip: Use the department filter to find decision-makers — skip interns and assistants by filtering for “Management” or “C-Suite.”

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How to Use Hunter.io Email Finder

Email Finder lets you look up the verified email address for any specific person at a company.

Here’s how to use it step by step.

Watch Email Finder in action:

Now let’s break down each step.

Step 1: Navigate to Email Finder

Click “Email Finder” in the left sidebar.

You’ll see two input fields: Full Name and Company Domain.

Step 2: Enter Name and Domain

Type the person’s first and last name in the Name field.

Enter the company domain (e.g., stripe.com) in the Domain field.

Here’s what this looks like:

✓ Checkpoint: Hunter.io will display a verified email address with a confidence score percentage.

Step 3: Save or Copy the Email

Click “Save” to add the contact to your Leads list.

Or copy the email address directly to use in your outreach tool.

✅ Result: You have a verified email address for your target contact, ready to use in any campaign.

💡 Pro Tip: A confidence score above 90% means the email is almost certainly valid — scores below 70% should be verified first.

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How to Use Hunter.io Email Verifier

Email Verifier lets you confirm whether an email address is valid before adding it to your outreach list.

Here’s how to use it step by step.

Watch Email Verifier in action:

Now let’s break down each step.

Step 1: Open the Email Verifier

Click “Email Verifier” in the left navigation menu.

You’ll see a single input box for entering an email address.

Step 2: Enter and Verify the Address

Type or paste the email address you want to verify.

Click the “Verify” button to run the check.

Here’s what this looks like:

✓ Checkpoint: Hunter.io returns one of three statuses: Valid, Risky, or Invalid.

Step 3: Act on the Result

Add “Valid” addresses directly to your Leads list or campaign.

Treat “Risky” emails with caution — they may exist but could harm deliverability.

Remove “Invalid” addresses immediately to protect your sender reputation.

✅ Result: Your email list is clean, verified, and ready to send without risking your domain reputation.

💡 Pro Tip: Re-verify lead lists every two months — people change jobs and email addresses go stale quickly.

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How to Use Hunter.io Campaigns

Campaigns lets you send personalized cold email sequences and automate follow-ups at scale.

Here’s how to use it step by step.

Watch Campaigns in action:

Now let’s break down each step.

Step 1: Connect Your Email Account

Go to Settings > Email Accounts and connect Gmail, Outlook, or SMTP.

Hunter.io will send emails directly through your connected account.

Step 2: Create a Campaign

Click “Campaigns” and then “New Campaign.”

Add your leads, write your subject line, and draft the first email.

Here’s what this looks like:

✓ Checkpoint: You should see your email sequence with at least one follow-up step added.

Step 3: Schedule and Launch

Set sending limits and schedule windows to avoid spam filters.

Click “Start Campaign” to begin sending automatically.

Track opens, clicks, and replies from the campaign dashboard.

✅ Result: Your cold email campaign runs automatically and follows up with non-responders without any manual work.

💡 Pro Tip: Adding one follow-up email alone can increase reply rates by up to 22% — always include at least two follow-up steps.

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How to Use Hunter.io Google Sheets Add-on

Google Sheets Add-on lets you run domain searches and email lookups directly inside your spreadsheets.

Here’s how to use it step by step.

Watch the Google Sheets Add-on in action:

Now let’s break down each step.

Step 1: Install the Add-on

Open Google Sheets and go to Extensions > Add-ons > Get Add-ons.

Search for “Hunter” and click Install.

Step 2: Connect Your Hunter.io Account

Go to Extensions > Hunter > Open and log in with your Hunter.io API key.

The add-on sidebar will appear on the right side of your sheet.

Here’s what this looks like:

✓ Checkpoint: The Hunter.io sidebar should show Domain Search and Email Finder options.

Step 3: Run Lookups from Your Sheet

Select a column of domains and click “Find Emails” to bulk-search in one pass.

Results populate directly into adjacent columns in your spreadsheet.

✅ Result: Your lead list in Google Sheets is now enriched with verified email addresses without switching tools.

💡 Pro Tip: Use the add-on to enrich CRM exports — paste a list of domains and get emails for every row automatically.

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How to Use Hunter.io Browser Extension

Browser Extension lets you find email addresses while browsing any company website or LinkedIn profile.

Here’s how to use it step by step.

Watch the Browser Extension in action:

Now let’s break down each step.

Step 1: Install the Chrome Extension

Visit the Chrome Web Store and search for “Hunter – Email Finder Extension.”

Click “Add to Chrome” and confirm the installation.

Step 2: Find Emails While Browsing

Visit any company website and click the Hunter icon in your browser toolbar.

Hunter.io instantly scans the domain and shows all available email addresses.

Here’s what this looks like:

✓ Checkpoint: A popup shows the email addresses found, their confidence scores, and save buttons.

Step 3: Save Contacts to Leads

Click the save icon next to any contact to add them to your Hunter.io Leads list.

All saved leads sync automatically to your Hunter.io account dashboard.

✅ Result: You can now find and save prospect emails without ever leaving the website you’re researching.

💡 Pro Tip: Use the extension on LinkedIn company pages to find corporate email patterns even when addresses aren’t directly listed.

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How to Use Hunter.io Bulk Tasks

Bulk Tasks lets you search or verify thousands of email addresses at once by uploading a CSV file.

Here’s how to use it step by step.

Watch Bulk Tasks in action:

Now let’s break down each step.

Step 1: Prepare Your CSV File

Create a CSV with a column for domains (for bulk domain search) or emails (for bulk verification).

Ensure each row has clean, properly formatted data before uploading.

Step 2: Upload and Configure the Task

Click “Bulk” in the left sidebar and select the task type — Domain Search or Email Verifier.

Upload your CSV and map the correct column to the input field.

Here’s what this looks like:

✓ Checkpoint: Hunter.io will show a preview of your uploaded data before processing begins.

Step 3: Download Results

Click “Launch” to start processing — large files may take a few minutes.

Once complete, download the enriched CSV with all results appended as new columns.

✅ Result: Thousands of domains or emails are searched and verified in one batch, saving hours of manual work.

💡 Pro Tip: Run bulk verification on any imported lead list before launching campaigns — clean lists dramatically reduce bounce rates.

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How to Use Hunter.io API Key

API Key lets you connect Hunter.io’s email finding and verification data directly to your own apps and workflows.

Here’s how to use it step by step.

Watch the API Key setup in action:

Now let’s break down each step.

Step 1: Generate Your API Key

Click “API” in the left sidebar to find your unique API key.

Step 2: Make Your First API Call

Use the key as a parameter in your HTTP request to Hunter.io’s API endpoints.

Example call: https://api.hunter.io/v2/domain-search?domain=stripe.com&api_key=YOUR_KEY

Here’s what this looks like:

✓ Checkpoint: The API returns a JSON response with email addresses, confidence scores, and contact details.

Step 3: Integrate with Your Tools

Connect the API to your CRM, Zapier, or custom scripts for automated lead enrichment.

Monitor your API usage from the dashboard to stay within plan limits.

✅ Result: Hunter.io data flows automatically into your sales stack without any manual copying or exporting.

💡 Pro Tip: Use the API with Zapier to auto-enrich new CRM contacts with verified emails the moment they’re added.

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How to Use Hunter.io AI Writing Assistant

AI Writing Assistant lets you draft personalized cold email copy faster using AI-powered suggestions inside the Campaigns editor.

Here’s how to use it step by step.

Watch the AI Writing Assistant in action:

Now let’s break down each step.

Step 1: Open a Campaign Email

Go to Campaigns and create a new campaign or open an existing one.

Click into the email body editor to open the writing interface.

Step 2: Use the AI Suggestion Tool

Click the AI icon inside the email editor to activate the assistant.

Enter a short prompt describing your goal and target audience.

Here’s what this looks like:

✓ Checkpoint: The AI generates a complete email draft you can edit, accept, or regenerate.

Step 3: Personalize and Send

Edit the AI draft to add specific details about the recipient or their company.

Add personalization tokens like {{first_name}} and {{company}} for automatic substitution.

✅ Result: You have a compelling, personalized cold email ready to send in under two minutes.

💡 Pro Tip: Always edit AI-generated emails to add one specific, personal detail about the prospect — generic AI copy rarely converts.

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Hunter.io Pro Tips and Shortcuts

After testing Hunter.io extensively, here are the best tips to work faster.

Keyboard Shortcuts

Action	Shortcut
Open Domain Search	Alt + D
Open Email Finder	Alt + F
Copy email address	Ctrl + C (after selecting)
Save contact to Leads	Click the bookmark icon

Hidden Features Most People Miss

Email Pattern Detection: Hunter.io shows the email format pattern a company uses (e.g., {first}.{last}@company.com) — use this to guess emails for contacts not in the database.
Follow Feature: “Follow” any company domain to receive alerts when new email addresses are discovered — great for staying on top of fast-growing teams.
Lead Notes: Add custom notes to each saved lead inside your Leads list — use this to track outreach status without needing a separate CRM.

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Hunter.io Common Mistakes to Avoid

Mistake #1: Sending to Low-Confidence Emails Without Verifying

❌ Wrong: Sending campaign emails to addresses with confidence scores below 70% without running them through the Email Verifier first.

✅ Right: Always verify any email with a score under 90% using the Email Verifier before adding it to a campaign — this protects your sender reputation.

Mistake #2: Using Generic Email Copy Without Personalization

❌ Wrong: Blasting the same copy to every contact without customizing the opening line or referencing the recipient’s role or company.

✅ Right: Use personalization tokens in Campaigns and add at least one specific detail about each recipient — personalized emails get up to 26% higher open rates.

Mistake #3: Skipping Follow-Up Emails

❌ Wrong: Sending only one email per prospect and assuming no reply means they’re not interested.

✅ Right: Set up at least two follow-up steps in your Campaigns sequence — a single follow-up alone can raise response rates by 22%.

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Hunter.io Troubleshooting

Problem: No email addresses found for a domain

Cause: The company uses a private email server, or their addresses haven’t been indexed by Hunter.io.

Fix: Try searching the company name directly rather than the domain. If still no results, use the Email Finder with a known employee’s name to generate a pattern-based guess.

Problem: Campaign emails landing in spam

Cause: Sending too many emails per day, using spam trigger words, or contacting unverified addresses.

Fix: Limit daily sends to under 50 emails per connected account, verify all addresses first, and warm up new email accounts before launching large campaigns.

Problem: API not returning results

Cause: Incorrect API key format, exceeded request limits, or a malformed endpoint URL.

Fix: Double-check your API key in Settings > API, review the official Hunter.io API documentation for correct endpoint formatting, and check your plan’s monthly request quota.

📌 Note: If none of these fix your issue, contact Hunter.io support via the live chat on their website.

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What is Hunter.io?

Hunter.io is a lead generation and email outreach tool that helps you find, verify, and contact professional email addresses at any company.

Think of it like a search engine for business email addresses — built specifically for sales teams, recruiters, and marketers.

Watch this quick overview:

It includes these key features:

Domain Search: Find all publicly indexed email addresses linked to any company website.
Email Finder: Get a verified email for any specific person using their name and company domain.
Email Verifier: Confirm whether an address is valid before sending to protect deliverability.
Campaigns: Send automated, personalized cold email sequences with built-in follow-ups.
Bulk Tasks: Upload a CSV to search or verify thousands of emails in one batch.
API Key: Integrate Hunter.io data into your own tools, CRMs, and automations.

For a full review, see our Hunter.io review.

Try Hunter IO for free

Hunter.io Pricing

Here’s what Hunter.io costs in 2026:

Plan	Price	Best For
Free	$0/month	Individuals testing the tool with limited searches
Starter	$34/month	Freelancers and solo sales reps doing regular prospecting
Growth	$104/month	Small teams running active outreach campaigns at volume
Business	$209/month	Growing sales teams needing higher limits and API access
Enterprise	Custom	Large organizations with custom volume and compliance needs

Free trial: Yes — the Free plan gives 25 monthly searches with no credit card required.

Money-back guarantee: Contact support within a reasonable period after purchase for a refund review.

💰 Best Value: Growth plan — the jump from Starter gives significantly higher search and verification limits for active outreach teams.

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Hunter.io vs Alternatives

How does Hunter.io compare? Here’s the competitive landscape:

Tool	Best For	Price	Rating
Hunter.io	Email finding and verification	$34/mo	⭐ 4.5
Instantly	High-volume cold email sending	$37/mo	⭐ 4.7
Snov.io	All-in-one prospecting and drip campaigns	$30/mo	⭐ 4.5
Apollo	Full sales intelligence platform	$49/mo	⭐ 4.8
Reply.io	Multichannel sales sequences	$59/mo	⭐ 4.6
UpLead	High-accuracy B2B contact data	$99/mo	⭐ 4.7
Mailshake	Simple cold email outreach	$58/mo	⭐ 4.6
Lemlist	Personalized image and video emails	$59/mo	⭐ 4.6

Quick picks:

Best overall: Apollo — combines contact data, sequencing, and CRM in one platform.
Best budget: Hunter.io Free — 25 searches/month at no cost, no card needed.
Best for beginners: Hunter.io — clean interface and the simplest onboarding in the category.
Best for high-volume sending: Instantly — built specifically for agencies and teams sending at scale.

🎯 Hunter.io Alternatives

Looking for Hunter.io alternatives? Here are the top options:

🚀 Instantly: Best for agencies and teams sending thousands of cold emails per day with unlimited sending accounts.
💰 Snov.io: Affordable all-in-one tool combining email finding, verification, and drip sequences under one plan.
🌟 Apollo: The most complete sales platform — contact database, sequences, CRM, and analytics all built in.
⚡ Reply.io: Multichannel outreach platform covering email, LinkedIn, and calls in a single automated sequence.
🎯 UpLead: Guarantees 95% data accuracy and offers real-time email verification on every contact exported.
📊 Mailshake: Clean, beginner-friendly cold email tool with strong deliverability coaching built into the interface.
🎨 Lemlist: Stands out for personalized image and video email campaigns that boost reply rates significantly.
🔧 Woodpecker: Developer-friendly cold email platform with strong API support and smooth CRM integrations.
🧠 Smartlead: AI-powered warm-up and sending rotation across unlimited inboxes for maximum deliverability.
🏢 Saleshandy: Feature-rich cold email platform with a generous free trial and strong inbox rotation tools.
⭐ Klenty: Sales engagement platform with deep CRM integrations and powerful cadence personalization features.
🔒 Warmbox: Specialized email warm-up service to build sender reputation before launching cold outreach campaigns.
💼 Maildoso: Done-for-you cold email infrastructure with managed domains and inbox setup for agencies.
🔥 Manyreach: Unlimited email account sending with built-in warm-up at a flat monthly rate for high-volume teams.
👶 Warmy: Easiest email warm-up tool on the market — ideal for anyone launching their first cold outreach campaign.

For the full list, see our Hunter.io alternatives guide.

⚔️ Hunter.io Compared

Here’s how Hunter.io stacks up against each competitor:

Hunter.io vs Instantly: Hunter.io wins for finding and verifying emails; Instantly wins for high-volume sending with unlimited accounts.
Hunter.io vs Snov.io: Both are similar in price and features; Hunter.io has a cleaner interface while Snov.io offers more drip sequence options.
Hunter.io vs Apollo: Apollo offers a much larger contact database and full CRM; Hunter.io is simpler and better suited for focused email finding.
Hunter.io vs Reply.io: Reply.io covers more channels (LinkedIn, calls, SMS); Hunter.io is better for email-only outreach with a lower price point.
Hunter.io vs UpLead: UpLead provides richer contact profiles with phone numbers; Hunter.io is more affordable and better for pure email discovery.
Hunter.io vs Mailshake: Mailshake is a stronger campaign execution tool; Hunter.io is stronger for finding the emails in the first place.
Hunter.io vs Lemlist: Lemlist wins for creative personalization with images and videos; Hunter.io wins for straightforward email finding and verification.
Hunter.io vs Woodpecker: Woodpecker is better for agency-scale multi-client campaign management; Hunter.io is the better data sourcing tool.
Hunter.io vs Smartlead: Smartlead excels at inbox rotation and deliverability at scale; Hunter.io is the better choice for email prospecting and verification.
Hunter.io vs Saleshandy: Saleshandy has stronger campaign features for outbound teams; Hunter.io is the better dedicated email finder.
Hunter.io vs Klenty: Klenty is a more complete sales engagement platform; Hunter.io is the better pick for teams that already have a CRM.
Hunter.io vs Warmbox: These tools complement each other — use Hunter.io to find emails and Warmbox to warm up your sending domain before outreach.
Hunter.io vs Maildoso: Maildoso is a full infrastructure provider for agencies; Hunter.io is the better self-service email finding and campaign tool.
Hunter.io vs Manyreach: Manyreach offers unlimited sending accounts at a flat rate; Hunter.io is the better tool when email discovery is the primary need.
Hunter.io vs Warmy: Warmy focuses entirely on email warm-up; Hunter.io covers the full workflow from finding emails to sending campaigns.

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Start Using Hunter.io Now

You learned how to use every major Hunter.io feature:

✅ Domain Search
✅ Email Finder
✅ Email Verifier
✅ Campaigns
✅ Google Sheets Add-on
✅ Browser Extension
✅ Bulk Tasks
✅ API Key
✅ AI Writing Assistant

Next step: Pick one feature and try it now.

Most people start with Domain Search.

It takes less than 5 minutes.

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Frequently Asked Questions

What is Hunter.io used for?

Hunter.io is used to find and verify professional email addresses so you can contact the right people at any company. Sales teams use it for prospecting, recruiters use it for outreach, and marketers use it to build lead lists. It also includes a Campaigns feature for sending automated cold email sequences directly from the platform.

Is Hunter.io legal?

Yes, Hunter.io is legal — it collects email addresses only from publicly available sources on the web. It is GDPR-compliant and includes built-in data protection measures to help users stay compliant with privacy regulations. Always ensure your own outreach follows the email laws applicable in your target country.

Is Hunter.io worth it?

Hunter.io is worth it for anyone doing consistent email prospecting or outreach. The accuracy is high, the interface is simple, and the free plan is genuinely useful for testing. Paid plans become cost-effective once you’re running regular campaigns with 100+ contacts per month.

How to get Hunter.io for free?

Hunter.io offers a free plan with 25 email searches and 50 verifications per month — no credit card required. Simply sign up at hunter.io with your email address to activate it immediately. The free plan also includes access to the browser extension and Google Sheets add-on.

How to check if an email is legit?

Use Hunter.io’s Email Verifier to check if any email address is valid. Enter the address and Hunter.io returns a status of Valid, Risky, or Invalid based on real-time checks of the mail server. A “Valid” result with a high confidence score means the address exists and is safe to contact.

How does Hunter.io find emails?

Hunter.io finds email addresses by crawling publicly available web pages, professional directories, and published documents. It indexes these addresses and matches them to company domains, building a searchable database updated continuously. The tool also detects email format patterns at each company, which it uses to generate likely addresses even when a specific contact isn’t indexed.