Bulk Email Verifier
Upload your list once and get back a clean, send-ready file — every address checked against live mail servers, every original column preserved, duplicates and unknowns never charged.
Verify thousands of emails without babysitting the tab
Upload a CSV or TXT file with up to 10,000 addresses and TrueSendy verifies it on the server — not in your browser. Close the tab, reload the page, come back tomorrow: the job keeps running, and your finished file waits in Tasks & Results, ready to download for 7 days.
Most verifiers hand back a stripped-down file with only the addresses they liked. TrueSendy returns every column you uploaded — names, companies, tags, everything — with the verification result appended to each row, so the clean file drops straight back into your CRM or sending platform.
Nothing gets charged twice
The same address appearing five times in one file is verified once. Duplicates are copied from the first result and cost nothing — and unknown results, where the mail server would not answer clearly, are never charged at all.
Any CSV works
The email column is detected automatically, quoted fields survive intact, and headerless files keep every row — the first address is never eaten as a fake header.
How bulk verification works
Upload or paste
Drag in a CSV or TXT file, or paste your addresses and give the task a name so you can find it later.
We verify on the server
Every address runs the full six-check pipeline against live mail servers, with live progress and credits debited per verified row.
Download the full file
Your original columns plus truesendy_status, score, provider and detail for every row. Segment it however you send.
The six checks inside every verification
Syntax & format
Malformed addresses and typos are caught instantly, before any network check runs.
Disposable detection
Temporary inboxes from throwaway providers are flagged so they never pollute your list.
Role account detection
Addresses like info@, support@ and admin@ are identified — they behave differently from personal mailboxes.
MX & provider detection
We resolve the domain's mail servers and identify the provider behind it — Gmail, Microsoft 365, and thousands more.
Catch-all probing
A random address is tested against the domain to learn whether it accepts everything, so catch-alls are labelled, not guessed.
Live SMTP handshake
Our own Port 25 engine speaks directly to the receiving mail server and asks whether the mailbox exists.
Simple, honest pricing
1 verification = 1 credit, credits never expire, and you are never charged for unknown results or for duplicate rows inside a bulk file.
Need a steady volume? Monthly plans run from $29/month for 25,000 credits. Or use the pricing calculator on the homepage to buy the exact number of credits you need.
Frequently asked questions
How many emails can I verify in one file?
Up to 10,000 rows per file. Bigger lists can be split across several tasks — each one runs on the server and is stored separately in Tasks & Results.
Am I charged for duplicate addresses in my file?
No. Duplicates inside the same file are verified once; every repeat is filled in from the first result for free. You are also never charged for results that come back unknown.
What do I get back when the job finishes?
A CSV with all of your original columns, untouched, plus four added columns: truesendy_status, truesendy_score, truesendy_esp and truesendy_detail. Nothing from your upload is dropped.
How long is my verified file kept?
Finished files stay available in Tasks & Results for 7 days, then they are deleted automatically. Download your results within that window.
What file formats are supported?
CSV and TXT, with or without a header row. The email column is found automatically; you can also paste addresses directly instead of uploading.
Start cleaning your list today
Create your free account in under a minute. 100 verification credits are on us — no card required.
Create free account