Email list cleaning tool that checks a CSV in your browser

Drop a lead CSV into this email list cleaning tool to find duplicates, typos, role addresses, and throwaway domains before you verify.

Drop a lead CSV hereCheck a lead CSV
A header row, then up to 100,000 rows.
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Read in your browser. Nothing is uploaded or stored.

What it checks
Rows
Every data row in the file, after the header. Blank lines are skipped.
No email
Rows where the email column is empty.
Duplicate emails
The same address more than once. Counted two ways: exactly as written, and ignoring case. The domain is never case sensitive. The part before the @ may be in theory, but the standard discourages using that, so Jane@ and jane@ are almost always one person.
Invalid syntax
Addresses that do not match the format the HTML standard uses for email fields: letters, digits and a few symbols before one @, and dot-separated domain labels of letters, digits and inner hyphens after it.
Too long
A part before the @ longer than 64 characters, or a domain longer than 255. Both are over the maximum the SMTP standard sets.
Domain without a dot
A domain with no dot, such as acme, passes the form check, but ICANN prohibits dotless domain names on new top-level domains, so it is almost always a typo or an internal name.
Example and test domains
example.com, example.net, example.org and anything under .test, .example, .invalid or .localhost. They are reserved for documentation and testing, so an address there is a placeholder.
Role addresses
Addresses whose part before the @ names a job or an inbox, not a person: info@, sales@, support@, noreply@. They are likely a shared inbox, not one person.
Free-mail addresses
Personal webmail and ISP mailboxes (gmail.com, outlook.com, a broadband provider's mail). The person may be real, but the address says nothing about their employer.
Disposable domains
Throwaway inbox services. Matched against a short set of well-known ones from a public blocklist, so a clean result here does not prove an address is not disposable.
Company density
How many rows share each company, from the company column, or from the email domain when there is none (free-mail domains are left out). It shows whether a few companies hold most of the list.
Title spread
The most common titles, and how senior the list is: each title is ranked by the most senior rank word in it (chief or founder, VP, head, director, manager, senior), the same fixed rule the account People tab uses. A title with no rank word counts as other.
Marketing and sales inboxes (106)

acquisition, ads, ads-account-noreply, advertise, advertise-noreply, advertising, advertisingsales, adwords, affiliate, affiliates, agency, agents, ambassador, ambassadors, b2bdata, bizdev, brand, branding, brandsolutions, businessdevelopment, campaign, campaigns, channel-sales, commercial, commerciale, competition, content, corporatesales, creative, deals, digital, ecommerce, enews, franchise, fundraising, growth, insidesales, leads, marketing, marketing-ops, marketing-team, marketingteam, marketplace, media, merchants, mkt, mktg, news, newbiz, newbusiness, newsletter, newsletters, newsletters-noreply, offers, outreach, partner, partners, partnerships, ppc, pr, presales, press, presse, promo, promotions, publicidade, publisher, publishers, publishing, referrals, reklama, retail, sale, sales, sales-team, sales.team, sales1, sales2, salesengineers, salesforce, salesops, salesteam, sem, seo, shop, shopify, shopping, social, socialmedia, sponsorship, store, store-news, subscribe, subscriptions, team-sales-enablement, trade, update, updates, vendas, vendas1, vendas2, ventas, ventas1, ventas2, verkauf, wholesale

Support, notification and no-reply inboxes (167)

abm-alerts, abuse, admin, administrator, administrators, admins, alarm, alarms, alert, alerts, alerts-noreply, alerts-qa, announce, announcements, arin-abuse, atencionalcliente, atendimento, auto-confirm, automated, automated.testing, bugs, calendar-notification, care, chat, chat-noreply, chatter, clientservices, comments-noreply, complaints, contact, contact-us, contactenos, contacto, contactus, contato, crm, customer, customer.service, customercare, customerfeedback, customerservice, customerservicecenter, customerservices, customersuccess, customersupport, custserv, digest, dispatch, dns, do-not-reply, do_not_reply, docs, domain, domainmanagement, domains, donotreply, download, drive-shares-dm-noreply, editors-noreply, emergency, english-personalized-digest, error, errors, faq, feedback, google-workspace-alerts-noreply, googlealerts-noreply, groups-noreply, help, helpdesk, hit-reply, hostmaster, info, infopremium, informacion, informatica, information, informatique, informativo, inquiries, inquiry, instant-updates, internal-noreply, ispfeedback, ispsupport, ithelp, itsupport, jira, jobalerts-noreply, jobs-noreply, junk, kundeservice, looker-studio-noreply, mailer, mailer-daemon, mailerdaemon, maintenance, membersuccess, messages-noreply, messaging-digest-noreply, monitor, monitoring, news-noreply, no-reply, no-reply-forms, no.replay, no.reply, no.reply.alerts, no_reply, noc, noreply, noreply-apps-scripts-notifications, noreply-dmarc, noreply-spamdigest, noresponse, notificaciones, notification, notification.external, notifications, notifications-noreply, notify, outage, phish, phishing, pkginfo, pullrequests-reply, questions, reminder, reminders, report, reporting, reports, request, requests, response, rsreply, sc-noreply, security, selectsupport, sellersupport, service, serviceclient, servicedesk, services, servicioalcliente, soporte, spam, suggestions, suporte, support, support-team, supportteam, survey, sysadmin, system, systemmessage, systems, tech, technical, techsupport, tickets, unsubscribe, voice-noreply, voicemail, webmaster, webnotification, workspace-noreply

Booking and event inboxes (22)

appointments, booking, bookings, calendar, conference, event, events, invitations, invites, meeting, meetup, reserva, reservaciones, reservas, reservation, reservations, rezervari, rsvp, schedule, webinar, webinars, workshop

Team, department and other shared inboxes (721)

123, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023, 2024, 2025, 2026, 2027, 2028, 2029, 2030, aaa, abc, academy, accessibility, account, account-services, accountant, accounting, accountmanager, accountmanagers, accounts, accountspayable, adm, admin1, administracao, administracion, administrador, administratie, administratif, administration, administrativo, adminteam, admisiones, admissions, adops, advice, advisor, advisors, all, all-employees, all-pms, all-staff, all-team, all-users, all.employees, all.staff, all.users, all_staff, alla, alle, allemployees, allhands, allsales, allstaff, allstudents, allteachers, allteam, allusers, alpha, alphas, alumni, amministrazione, analysts, analytics, android, angels, animation, ap, api, app, apple, application, applications, apply, apps, archives, arin, asd, asdasd, asdf, asistente, ask, asset, assistanthead, assistencia, assistenza, associates, associates-all, ateam, auctions, automation, available, backend, backend-dev, backup, bd, benefits, berlin, bestellung, beta, biblioteca, bibliotheque, billing, bills, biuro, biz, boston, bot, buchhaltung, bulletins, business, business_team, butik, ca, caltrain, campusteam, capacitacion, captain, captains, career, careers, catering, central, centro, ceo, ceos, chartering, chef, chicago, china, church, citymanagers, class, classof2016, classof2017, classof2018, classof2019, classroom, classroom_teachers, client, clientes, clinic, cloud, cm, co-op, coach, coaches, coaching, code, colaboradores, colegio, com, comenzi, comercial, comercial1, comercial2, comments, commissions, committee, comms, communication, communications, community, company, company.wide, compete, compliance, compras, compta, comptabilite, comunicacao, comunicacion, comunicaciones, comunicazione, concierge, connect, consultant, consultas, consulting, consultoria, contabil, contabilidad, contabilidade, contabilita, contador, contractor, contractors, contracts, controller, coordinator, copyright, core, coreteam, corp, corporate, council, courrier, course, courses, crew, cs, csm, csteam, cultura, culture, customers, daemon, data, database, delivery, demo, denver, departures, deploy, deputy, deputyhead, design, designer, designers, dev, developer, developers, development, devnull, devops, devs, devteam, digsitesvalue, direccion, direction, directo, director, directors, directory, diretoria, direzione, discuss, diversity, donations, donors, dreamteam, editor, editorial, editors, education, eletters, email, emails, employment, eng, eng-all, engagement, engenharia, engineering, engineers, english, enq, enquire, enquires, enquiries, enquiry, enrollment, enterprise, envio, equipe, equipo, escritorio, europe, everybody, everyone, exec, execs, execteam, executive, executives, expenses, expert, experts, export, express, facebook, facilities, facturacion, faculty, family, farmacia, faturamento, fax, fbl, fellows, finance, financeiro, financeiro2, finanzas, firmapost, fiscal, food, football, form-submission, founders, france, friends, frontdesk, frontend, frontoffice, fte, ftp, fulfillments, fulltime, fun, fund-ops, geeks, general, geral, gerencia, giving, global, gm, grants, graphics, group, hackathon, hackers, head, head.office, headoffice, heads, headteacher, hello, hi, highschool, hiring, hola, home, homes, hosting, hotel, house, hq, hr, hr.dept, hrdept, hsstaff, hsteachers, human_resources, humanresources, ideas, ifttt, implementation, import, inbound, inbox, india, infor, infra, infrastructure, ingenieria, innkeeper, innovation, inoc, insights, instagram, instructor, insurance, integration, integrations, intern, internal, international, internet, interns, internship, invest, investment, investor, investorrelations, investors, investorservices, invoice, invoices, invoicing, ios, iphone, ir, it, itunes, job, jobs, jobs-listings, join, jornalismo, kontakt, la, lab, laboratorio, labs, ladies, latam, launch, lead, leaders, leadership, leadership-team, leadershipteam, learn, learning, leasing, legal, letters, library, licensing, lifesum, links, list, list-request, listingupdates, listmanager, listproc, listserv, loan-ops, login, loginotp, logistica, logistics, logistiek, lt, lunch, mail, mailbox, maildaemon, mailing, mailman, majordomo, management, management-group, management.team, management_team, manager, managers, master, mayor, md, member, members, memberservices, membership, mentor, mentors, merchant, metrics, mgmt, middleschool, misc, mobile, montreal, moreinfo, msstaff, msteachers, mt, music, myplex, namecheap, network, newyork, nntp, no, nobody, noemail, none, northamerica, nospam, notes, nps, null, ny, nyc, nyoffice, offboarding, office, officeadmin, officemanager, officers, officestaff, offtopic, oficina, onboarding, online, onsite, ooo, operaciones, operations, ops, order, orders, ordini, owners, parents, paris, parts, pastor, pay, payment, payments, paypal, payroll, pd, people, peoplemanagers, peopleops, per, performance, personnel, photos, planning, platform, plex, plex.tv, pm, portfolio, post, postbox, postfix, postmaster, prefeitura, presidencia, president, presidente, prime, principa, principal, principals, privacy, procurement, prod, produccion, product, product-team, product.growth, product.management, product.managers, product.team, production, productmanagers, products, productteam, produto, professor, program, programs, project, projectmanagers, projects, protocollo, proveedores, purchase, purchases, purchasing, qa, qualidade, quotes, random, receipts, recepcion, reception, receptionist, recommendations, recruit, recruiter, recruiters, recruiting, recruitment, recrutement, recursoshumanos, redacao, redaccion, redaction, redazione, reg, register, registrar, registration, revenue, rfp, rh, ripe-abuse, rnd, rockstars, root, rrhh, sac, sanfrancisco, school, schooloffice, science, sdr, se, search, seattle, secretaria, secretariaat, secretaris, secretary, sekretariat, seniors, server, sf, sf-office, sfo, sfoffice, sfteam, shareholders, shipping, signup, signups, singapore, sistemas, site, smile, smtp, socialclub, socios, software, solutions, sos, sport, squad, staff, startups, stats, stay, stockholm, stories, strategy, stripe, student, students, studio, study, submissions, submit, success, superintendent, supervisor, supervisors, supply, suprimentos, sydney, ta, talent, tax, teacher, teachers, team, teamleaders, teamleads, technik, technology, techops, techteam, tecnologia, tesoreria, test, testgroup, testing, the.principal, theoffice, theteam, time, timesheets, todos, tools, tour, trainers, training, transport, travel, treasurer, tribe, trustees, turismo, twitter, uk, undisclosed-recipients, us, usa, usenet, user, users, usteam, uucp, ux, vendors, volunteer, volunteering, volunteers, vorstand, warehouse, watercooler, web, webadmin, webdesign, webdev, website, webteam, welcome, whois, women, wordpress, work, writers, www, www-data, zakaz, zentrale

Free-mail and ISP domains (100)

gmail.com, googlemail.com, yahoo.com, yahoo.co.uk, yahoo.co.in, yahoo.co.jp, yahoo.com.br, yahoo.com.au, yahoo.ca, yahoo.fr, yahoo.de, yahoo.es, yahoo.it, ymail.com, rocketmail.com, hotmail.com, hotmail.co.uk, hotmail.fr, hotmail.de, hotmail.es, hotmail.com.br, outlook.com, outlook.fr, outlook.de, outlook.com.br, live.com, live.co.uk, live.fr, msn.com, icloud.com, me.com, mac.com, aol.com, protonmail.com, proton.me, tutanota.com, zoho.com, fastmail.com, gmx.com, gmx.de, gmx.net, mail.com, mail.ru, bk.ru, list.ru, inbox.ru, yandex.ru, yandex.com, rambler.ru, ukr.net, qq.com, foxmail.com, 163.com, 126.com, sina.com, sohu.com, naver.com, daum.net, hanmail.net, rediffmail.com, seznam.cz, wp.pl, o2.pl, onet.pl, interia.pl, abv.bg, walla.co.il, comcast.net, verizon.net, att.net, sbcglobal.net, bellsouth.net, cox.net, charter.net, earthlink.net, optonline.net, btinternet.com, sky.com, virginmedia.com, orange.fr, wanadoo.fr, free.fr, sfr.fr, laposte.net, libero.it, virgilio.it, tin.it, t-online.de, web.de, freenet.de, bluewin.ch, ziggo.nl, telenet.be, terra.com.br, uol.com.br, bol.com.br, shaw.ca, rogers.com, bigpond.com, optusnet.com.au

Disposable inbox domains (49)

mailinator.com, guerrillamail.com, guerrillamail.net, guerrillamail.org, guerrillamail.de, guerrillamailblock.com, sharklasers.com, grr.la, 10minutemail.com, 10minutemail.net, temp-mail.org, yopmail.com, yopmail.fr, yopmail.net, trashmail.com, trashmail.de, trashmail.net, getnada.com, nada.email, maildrop.cc, dispostable.com, throwawaymail.com, fakeinbox.com, mintemail.com, mohmal.com, emailondeck.com, mailnesia.com, tempr.email, discard.email, mailcatch.com, getairmail.com, tempmailo.com, mytemp.email, spambox.us, tempinbox.com, mailpoof.com, moakt.com, emailfake.com, fakemail.net, inboxkitten.com, mail.tm, 1secmail.com, tempail.com, mailsac.com, spam4.me, pokemail.net, jetable.org, harakirimail.com, wegwerfmail.de

Reserved example and test names (7)

example.com, example.net, example.org, anything under .test, anything under .example, anything under .invalid, anything under .localhost

Seniority words, most senior first
Executive
chief, ceo, cfo, cto, coo, cro, cmo, cio, ciso, cpo, founder, co-founder, cofounder, owner, president, managing director, general manager, managing partner, general partner, founding partner
VP
evp, svp, avp, vp, v.p., vice president, vice-president
Head
head
Director
director
Manager
manager
Senior
senior, sr, lead, principal
Photo of Utku Zihnioglu

By

ยท CEO & co-founder

Updated Nov 11, 2026

Shorter page: the tool first, the answer in a few lines.

An email list cleaning tool should catch what the file already gives away before you pay to verify a single address. Drop a lead CSV above to see its duplicates, addresses nobody can send to, role and free-mail addresses, and throwaway domains. Your browser reads the file, and nothing is uploaded.

It never verifies. Whether a mailbox exists, or a domain accepts every address, only the receiving server can say. Treat the report as a diagnosis, then verify what survives it.

How to read the report

Start with duplicates, including copies that differ only by capital letters, such as Jane.Doe@ and jane.doe@. The SMTP standard, RFC 5321, tells mail systems not to rely on case, so those are one person, and most dedupe steps miss them.

Addresses with bad syntax, a domain with no dot, or an example domain cannot be sent to as written. Look them up again rather than guess a fix. Role and free-mail addresses are judgment calls for each campaign.

The company and title panels show who is on the list. When a few companies hold most of it, several people at one company are about to get the same email on the same morning.

Clean in this order

  1. Lowercase the email column, then remove duplicates. Every later step counts per address.

  2. Delete, or look up again, every address that cannot be sent to as written.

  3. Decide on role and free-mail addresses for this campaign.

  4. Verify what is left, and send only to the addresses that come back deliverable.

After the first send, read each bounce in the bounce code decoder. Contacts with no email at all? See finding verified emails for a whole list.

Email list cleaning tool: common questions

What is a catch-all domain?

A catch-all domain accepts mail sent to almost any address at it, so a verifier cannot confirm that one particular mailbox is real. Treat a catch-all result as a soft yes, and send to it only when the rest of the contact checks out.

Should I remove role addresses like info@ from my list?

For cold outreach, usually. A role address reaches a shared inbox, not the person you researched, and nobody owns the reply. Look first, though: an info@ at a five-person company may be the founder's own inbox.

Should I remove free-mail addresses from a B2B list?

Not without a look. A consultant may run a whole business from a gmail.com address. For cold outreach, keep the person and find their work address instead.

About this article

Photo of Utku Zihnioglu

Utku Zihnioglu

CEO & co-founder

Serial entrepreneur who built infrastructure companies handling billions of requests. Now leads engineering at Oneprofile, which finds the people worth talking to, researches each one, and follows up until they reply.

Drafted with AI from our product docs and code. Utku Zihnioglu answers for what it says.

Fix these in a table: import, verify, dedupe

Import the CSV into Oneprofile, keep one row per address, and verify the rest.

Free plan: 200 credits a month, 3 integrations, no card

Fix these in a table: import, verify, dedupe

Import the CSV into Oneprofile, keep one row per address, and verify the rest.

Free plan: 200 credits a month, 3 integrations, no card