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Sales & Customers · Lead Generation & Prospecting

Contact Discovery

8 paid against 9 free you can run yourself.

Paid against free › Sales & Customers › Lead Generation & Prospecting › Contact Discovery · Talking to customers on Repo Radar

Contact discovery tools find the work email, and often the phone number, of a person you want to reach. Paid tools sell access to a licensed people database or a waterfall of providers, priced by credits or lookups; open-source projects either guess and verify addresses themselves, gather what is published on the web, or orchestrate the paid providers with your own keys.

Paid 8 reviewed · 2 related

Prices and free tiers as checked, dated on each review.

HHunter

All-in-one email outreach platform for finding, verifying, and contacting leads.

$49free tierLLusha

B2B contact data and sales intelligence for GTM teams and AI agents.

$37.45free tierRRocketReach

Find emails, phones, and social profiles for 700M+ professionals.

$33free tierCContactOut

Find verified emails and phone numbers for B2B outreach.

$49free tierKKaspr

Kaspr is a B2B prospecting tool providing verified contact data via LinkedIn extension and API.

free tierPProspeo

Verified B2B emails and mobile numbers for sales outreach.

free tierFFindymail

Findymail finds and verifies B2B emails and phone numbers with a guaranteed low bounce rate.

$99free tierFFullEnrich

Waterfall enrichment platform for verified B2B emails and phone numbers.

$55free tier

Related paid tools

Their home is another job; they cover part of this one too.

AApollo

AI sales platform for B2B data, engagement, and outreach.

free tierSSnov.io

All-in-one AI lead generation and multichannel sales outreach platform.

$39free tier

Free 9 direct · 1 related

Free to use. You run it on your own server.

Direct alternatives

They do this job.

THlaramies/theHarvester

E-mails, subdomains and names Harvester - OSINT

★ 18kFreeCHreacherhq/check-if-email-exists

Check if an email address exists without sending any email, written in Rust. Comes with a ⚙️ HTTP backend.

★ 10.2kFreeEMbuyukakyuz/email-sleuth

Discover and verify professional emails using names + domains

★ 425FreeOPdebpalash/OpenGTM

Open-source, self-hosted alternative to Clay.com for lead sourcing, enrichment waterfalls, AI research, buying signals, and outbound automation.

★ 62FreeDANuclear-Marmalade/dataforge

Free open-source business data enrichment engine. The open-source alternative to Apollo, ZoomInfo, and Clearbit.

★ 58FreeENmasteranime/enrichment-kit

Open-source Clay.com alternative. Multi-vendor enrichment waterfalls — bring your own API keys, pay ~85% less per lead.

★ 42FreeOPSamyrrrrrr990/openleads

Open-source lead finder and cold email workspace. Describe a customer, get named people with labeled emails, then write, send, and automate it. No API keys, runs locally. Free Apollo and Hunter alternative.

★ 40FreeLEankaboot-source/leadminer

⛏ Leadminer - mine, clean & enrich contacts then send campaigns from your own email

★ 15FreeTRmeysam81/trawl

Trawl Chrome Extension. Free, privacy-first alternative to Hunter.io — extract, validate, and export emails from any web page.

★ 7Free

Related alternatives

A second choice: they cover part of this job or are a building block for it.

COethbak/connexion-for-linkedin

A free tool used to search for LinkedIn profiles with filters and to automate sending connection requests.

★ 35Free

Feature by feature

Every paid tool and free repository we compared, marked against the same features.

✓has itPartlysome plans or extra work—confirmed not available?not confirmed✓the vendor's claim onlypricingClick a mark for its note and source

Paid · 10Free · 10
Featurelaramies/theHarvesterreacherhq/check-if-email-existsbuyukakyuz/email-sleuthSamyrrrrrr990/openleadsdebpalash/OpenGTMmasteranime/enrichment-kiteracle/OpenOutreachankaboot-source/leadminerNuclear-Marmalade/dataforgemeysam81/trawl
Starts at$49 per month, billed monthly (Starter)$49 per seat per month, billed annually (Basic)$37.45 per month, billed yearly (Starter)$33 per month, $399 billed annually (Essentials)$39 per month, billed monthly (Starter)$49 per month (Email plan, reduced from $99)$49 per user per month (Starter)$49 per user per month, billed monthly (Starter)$99 per month (Individual)$55 per month, billed monthly (Pro, 1,000 credits)GPL-2.0MITMITAGPL-3.0AGPL-3.0MITGPL-3.0AGPL-3.0MITMIT
Discovery
Email finder from name and companyReturns a person's work email from their name and company or domain.
Domain searchLists the email addresses found for a company domain.
Phone numbersReturns direct or mobile phone numbers for a person.
People search with filtersSearches a people and company database by title, company, location and similar filters.
Workflow
Browser extensionReveals contact details while browsing LinkedIn or company websites.
Data quality
Email verificationChecks that an address is deliverable before it is used.
Waterfall enrichmentQueries several data providers in turn until one returns a result.
Workflow
Bulk list enrichmentEnriches an uploaded list of people (CSV or similar) in one job.
Integration
API accessProgrammatic lookups through a documented API or SDK.
CRM integrationPushes or syncs contacts to a CRM such as HubSpot or Salesforce.
MCP serverLets AI assistants such as Claude use the tool through the Model Context Protocol.
Extras
Email sequencesSends multi-step outreach from the same product.

Excluded candidates

Looked at, and left out of the comparison, with the reason.

Paid apps

  • ZoomInfoLarge enterprise sales intelligence platform with contact data and intent. Its pricing page offers plans only through a sales conversation, with no published price, so it cannot be compared on cost with the self-serve tools here.Source
  • CognismEuropean-focused B2B contact database with phone-verified mobiles. Every plan on its pricing page is sold through a sales call, so there is no published starting price to compare.Source
  • UpLeadB2B contact database with verified emails and phones and a 7-day test drive. At $99 a month for 170 credits on monthly billing it covers the same lookup job as RocketReach and Lusha at a higher price per contact, so it ranked below them.Source
  • Skrapp.ioEmail finder with a LinkedIn extension and domain search, from $29 a month billed annually. It covers the same email-only job as Hunter and Prospeo without phone numbers, so it ranked below them.Source
  • Anymail FinderEmail finder that charges only for verified results, from $29 a month for 400 credits. It overlaps closely with Findymail and Hunter and adds no phone data, so it ranked below them.Source
  • Voila NorbertEmail finder and verifier with API and bulk workers, from $39 a month billed yearly. It is an email-only tool with the same scope as Hunter, which offers a free plan and a larger database, so it ranked below.Source
  • SignalHireEmail and phone finder with a browser extension, from $69 a month for emails. It does the same LinkedIn-extension job as ContactOut and Kaspr, which publish simpler plans, so it ranked below them.Source
  • WizaExports LinkedIn and Sales Navigator searches with verified emails, with phones at $0.35 each or on an $83-a-month email plan. Its job overlaps Kaspr and ContactOut, so it ranked below them in this comparison.Source
  • ClaySpreadsheet workspace that orchestrates many data providers and AI research, from $167 a month. It is a broader workflow builder that buys contact data from others, so it belongs with enrichment orchestration rather than contact discovery.Source
  • DropcontactGDPR-focused enrichment that fills in emails for contacts already in your CRM or file, with custom pricing at higher volumes. It enriches existing lists rather than discovering new people, so it is not compared here.Source
  • LeadMagicAPI-first email and mobile finder with one credit pool, from $99 a month billed monthly. It covers the same pay-per-result job as FullEnrich and Findymail, so it ranked just below them.Source

Repositories

  • mishakorzik/MailFinderPython OSINT script that looks for an email from a first and last name. Its README states that the project is stopped, so it is not a maintained option.Source
  • VecterAI/reacher-xAgent that finds and qualifies people from their activity on X and LinkedIn and drafts messages. It discovers people on social platforms rather than their email or phone, so it fits social prospecting better than contact discovery.Source
  • WildSiphon/MailfoguessOSINT tool that guesses and verifies a person's email from their name and other details. It has had no commits since January 2024, and email-sleuth covers the same name-plus-domain job more recently.Source
  • krmbzds/guessmailRuby gem that generates likely email addresses for a name and domain. It generates candidates without the verification and batch mode that email-sleuth offers, and its last release was January 2025.Source
  • buildingopen/opengtmBroad go-to-market toolkit covering lead generation, ICP scoring, SEO health checks and outreach. Contact discovery is one small part of it, and debpalash/OpenGTM covers the enrichment workbook more fully.Source
  • JosieBot26/prospector-mcp-email-finderMCP server that finds and verifies business emails for AI assistants. It is a small single-purpose server with 12 stars and no commits since March 2026, so the broader openleads was preferred.Source
  • Josue87/EmailFinderCommand-line tool that searches engines for emails on a domain. The repository has been archived and its last commit was in March 2023.Source
  • emeth-/Email-PermutatorScript that finds an email by trying permutations and validating them. It has not changed since March 2021, so it is not a maintained option.Source
  • getsoyuz/soyuzProject described as an open-source Apollo.io alternative. It has had no commits since October 2023, so it is not a maintained option.Source
  • m8sec/CrossLinkedPenetration-testing tool that builds employee name lists for a company from search engine results. It produces names and username formats for security testing, not verified contact details.Source
  • initstring/linkedin2usernameOSINT tool that generates username lists for a company's employees from LinkedIn. It is built for security assessments and returns guessed usernames rather than emails or phones.Source
  • omkarcloud/website-email-contact-scraperScraper that pulls emails, phones and social links from a website into JSON. It returns company-level contacts from one site, which dataforge and trawl already cover in this comparison.Source
  • kaifcodec/user-scannerEmail and username OSINT suite that checks where an identity is registered. It investigates a known email rather than discovering the contact details of a prospect.Source

Gaps

What the research could not settle from the vendors' own pages.

What vendors don't publish

  • No vendor publishes an independently measured match rate or bounce rate for its data; Findymail promises under 5% bounce with a credit refund, others say "verified". Buyers cannot compare accuracy without running their own test list.Hunter, Apollo, Lusha, RocketReach, Snov.io, ContactOut, Kaspr, Prospeo, Findymail, FullEnrich · checked 2026-10-20 · source 1
  • Findymail's prospecting plans state usage as "generous" and as multiples (5x, 20x) of the Individual plan, without a number of emails or phones per month. Buyers comparing cost per contact have to use its separate credit plans instead.Findymail · checked 2026-10-20 · source 1
  • ContactOut's plan cards show a reduced monthly price but do not say whether it is billed monthly or annually, and "unlimited" emails and phones are subject to fair-use terms on a separate page. The real yearly cost and limits are unclear from the pricing page.ContactOut · checked 2026-10-20 · source 1
  • Kaspr offers API access only on request, on Starter and Business, without published rate limits or terms. Teams planning an integration cannot tell in advance what they will get.Kaspr · checked 2026-10-20 · source 1
  • Hunter's pricing page does not mention phone numbers at all. Teams that need to call prospects cannot confirm from the page whether any phone data is available.Hunter · checked 2026-10-20 · source 1
  • The open-source finders that verify by SMTP need outbound port 25, which most cloud hosts and home networks block; check-if-email-exists says larger volumes need SMTP proxies. Results from a laptop or cloud server may differ from what the README shows.reacherhq/check-if-email-exists, buyukakyuz/email-sleuth, Samyrrrrrr990/openleads, Nuclear-Marmalade/dataforge · checked 2026-10-20 · source 1

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