ESP finder
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Identify the email service provider behind an email or domain. See provider details, MX records, and a confidence score to support outreach and IT checks.
Scrape hundreds of webpages with the Thunderbit Chrome Extension in one click, try the Thunderbit API for free, or use our Web Scraping Service to save engineering time.
Automate Web Data Extraction FasterUse the Thunderbit Chrome extension to scrape pages in a couple clicks and extract structured data from websites, PDFs, and images. Export results to Sheets, Airtable, or Notion.
Install fromChrome Web Store
Automate Web Data Extraction Faster
Collect leads, product data, or listings from any website with Thunderbit’s AI Web Scraper. Use AI Suggest Fields to detect the right columns, scrape paginated pages, and pull extra details by visiting subpages; Thunderbit can also summarize, categorize, and format the extracted data.
Scrape content from webpages, PDFs, docs, and images, then export to Google Sheets, Airtable, or Notion for workflows your team already uses. Schedule recurring scrapes for monitoring, and keep datasets clean with structured outputs like URLs, emails, phone numbers, and dates.
How to Find an ESP Using Thunderbit
STEP 1Download and InstallDownload and install the Thunderbit Chrome Extension from the Thunderbit Chrome Extension Download Page. Once installed, log in or create a free account to get started.
STEP 2Open ExtensionOpen the Thunderbit Chrome Extension, then open the ESP Finder tool. In the "Enter Email or Domain" tab, enter one value in the "email_or_domain" field, such as an email address (user@example.com) or a domain (example.com). Review the input for accuracy before running the tool.
STEP 3Click the Find ESP ButtonClick the "Find ESP" button to run the detection. Thunderbit will return a table showing the input, the detected provider name, relevant MX records, a confidence level, and technical details. After results load, export the table to Excel, Google Sheets, Airtable, or Notion, or download it as CSV or JSON.
Learn how to identify an email service provider from an email address or domain
Detect the email service provider
ESP Finder lets you enter a single email address or a domain and returns the most likely email service provider behind it. It analyzes the domain’s email routing signals to determine which platform handles delivery. This is useful for marketers validating outreach targets, IT teams auditing vendor usage, and operators who need quick visibility into email infrastructure without digging through DNS tools.
Review MX records and technical evidence
Along with the provider name, ESP Finder surfaces relevant MX records and supporting technical details used for the identification. This helps you verify why a provider was selected and reduces guesswork when domains use multiple services or have complex routing. A confidence level is included so you can prioritize follow-up checks for ambiguous results and trust high-signal matches.
Qualify leads and plan outreach by provider
Use ESP Finder to segment prospects by email platform so you can tailor deliverability checks, warm-up plans, and messaging workflows. Sales and marketing teams can spot common providers across an account list, identify managed email setups, and flag domains that may require extra care. The table output makes it easy to compare inputs side by side and share findings with teammates.
Audit domains for IT and operations workflows
ESP Finder supports lightweight audits of partner, vendor, or subsidiary domains by showing which email provider is in use and the MX configuration behind it. IT and security teams can use the results to document infrastructure, validate migrations, and troubleshoot routing issues. The structured table output also works well for tracking changes over time in internal documentation or spreadsheets.
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What users say about Thunderbit
Taryn W.Growth Strategist@Thunderbit changed how I run competitor research. I click 'AI Suggest Fields,' and it builds a clean table across paginated results—no coding, no CSS. Huge time-saver when analyzing product data from long-tail marketplaces.
Miles T.Sales Development ConsultantI use Thunderbit to grab emails and phone numbers from directories. It extracts clean contact info in one click, and exporting to Sheets or Notion takes seconds. No extra setup, no coding—just usable data ready to work with.
Rhea C.E-commerce AnalystThunderbit helps me monitor SKU data across multiple pages. I scrape the listings, then use Subpage Scraping to pull full product specs, pricing, reviews, and stock. The AI organizes everything into columns I define.
Cassian B.Real Estate AdvisorThunderbit's Scheduled Scraper makes real estate tracking easier. I describe the interval in plain English, and it automatically pulls updated listings, prices, and links without touching the setup again. Simple and very practical.
Dorian B.Content & SEO SpecialistI use Thunderbit's Field AI Prompts to clean and tag scraped blog content. It extracts titles, authors, and even suggests categories. Works great across dynamic sites and subpages—perfect for building structured SEO datasets.
Lina K.Marketplace Operations LeadWe track SKUs from niche stores using Thunderbit. Cloud Scraping handles 50 pages at a time, and for login-required sites, we switch to browser mode. It’s fast, flexible, and doesn’t need ongoing maintenance or manual edits.
Jorge F.Inbound Sales ManagerThunderbit’s AI Autofill is a lifesaver. After scraping contact info, I use it to fill lead forms directly in my browser. I just select the tab, and it fills everything using the scraped row. No manual input needed.
Alina D.Freelance ResearcherI rely on Thunderbit for extracting data from PDFs, image-based sites, and infinite scroll pages. It handles messy formats with AI and delivers ready-to-export tables I can send to Google Sheets or Airtable in seconds.
Taryn W.Growth Strategist@Thunderbit changed how I run competitor research. I click 'AI Suggest Fields,' and it builds a clean table across paginated results—no coding, no CSS. Huge time-saver when analyzing product data from long-tail marketplaces.
Miles T.Sales Development ConsultantI use Thunderbit to grab emails and phone numbers from directories. It extracts clean contact info in one click, and exporting to Sheets or Notion takes seconds. No extra setup, no coding—just usable data ready to work with.
Rhea C.E-commerce AnalystThunderbit helps me monitor SKU data across multiple pages. I scrape the listings, then use Subpage Scraping to pull full product specs, pricing, reviews, and stock. The AI organizes everything into columns I define.
Cassian B.Real Estate AdvisorThunderbit's Scheduled Scraper makes real estate tracking easier. I describe the interval in plain English, and it automatically pulls updated listings, prices, and links without touching the setup again. Simple and very practical.
Dorian B.Content & SEO SpecialistI use Thunderbit's Field AI Prompts to clean and tag scraped blog content. It extracts titles, authors, and even suggests categories. Works great across dynamic sites and subpages—perfect for building structured SEO datasets.
Lina K.Marketplace Operations LeadWe track SKUs from niche stores using Thunderbit. Cloud Scraping handles 50 pages at a time, and for login-required sites, we switch to browser mode. It’s fast, flexible, and doesn’t need ongoing maintenance or manual edits.
Jorge F.Inbound Sales ManagerThunderbit’s AI Autofill is a lifesaver. After scraping contact info, I use it to fill lead forms directly in my browser. I just select the tab, and it fills everything using the scraped row. No manual input needed.
Alina D.Freelance ResearcherI rely on Thunderbit for extracting data from PDFs, image-based sites, and infinite scroll pages. It handles messy formats with AI and delivers ready-to-export tables I can send to Google Sheets or Airtable in seconds.
