Q: How accurate are the results?

<h2 id="whataresultmeans">What a result means</h2> <p>A lookup is a <strong>point-in-time signal</strong> from live network, mailbox, and data checks, not a permanent fact:</p> <ul> <li>A phone number can be active at lookup time and disconnected next week. Carriers recycle numbers constantly.</li> <li>An email server can accept a verification today and bounce a real mail tomorrow. Some servers (catch-all domains, some corporate filters) accept everything during verification and sort it out later, which is how "deliverable" can still bounce.</li> <li>Spam and risk scores are probabilities built from signals, not verdicts.</li> <li>Reverse lookups return what our sources hold. For some numbers, emails, and IPs that is nothing, and "no data found" is a normal answer.</li> </ul> <h2 id="aresultlookedwrong">A result looked wrong?</h2> <ul> <li><strong>One or two misses</strong> are expected with any validation provider, for the reasons above.</li> <li><strong>A pattern across real volume</strong> (many "valid" numbers disconnected, a big share of results empty) is something we want to see: write to us in the chat with the product you used and a few example inputs, and the team reviews it.</li> <li><strong>Credits charged on failed lookups</strong>: tell us in the chat; we can pull your recent lookups with per-row status and credits, and the team reviews any discrepancy.</li> </ul> <h2 id="comparingagainstanotherprovider">Comparing against another provider</h2> <p>Different providers refresh different sources at different times, so disagreements between vendors are normal and do not by themselves mean either is broken. If the gap is large on real volume, send us examples.</p>

Q: Batch uploads: process a CSV

<h2 id="howitworks">How it works</h2> <ol> <li>Go to <strong>Batch Upload</strong> in the dashboard.</li> <li>Upload your CSV, pick the product to run, and map the column.</li> <li>The platform processes the file in chunks with live progress: processed, successful, failed, duplicates.</li> <li>Download results from the batch page when it finishes, including filtered exports such as "valid only".</li> </ol> <p>Files up to roughly <strong>1 GB / 2 million rows</strong> are supported. Batch rows spend credits at the product's normal per-lookup cost, and duplicates inside a file are detected and not double-charged.</p> <h2 id="whatisnormal">What is normal</h2> <ul> <li>Large batches take a while. <strong>"Processing" with the counters moving is healthy.</strong></li> <li>Some rows failing is normal (malformed numbers, empty cells); the failed count with reasons is in your results.</li> </ul> <h2 id="whentocontactus">When to contact us</h2> <p>Write to us in the chat if a batch is stuck at the same count for a long time, failed outright, will not download, or spent credits that do not match the row counts. We can see your batch's live status on our side. Please do not re-upload a large file before checking with us: a re-uploaded file is a new job and can spend credits again, and we would rather fix the stuck job and review the credits with you.</p>

Question 1

Which products exist, and what works where

Accepted Answer

The product families

Phone: phone/number validation, HLR lookup (live network check), ported-number (MNP) lookup, number type, mobile finder, spam and risk score, DNC and compliance check, reverse phone lookup (which includes caller-name data where available), and number monitoring (watch lists re-checked on a schedule).
Email: email verification (deliverability), email enrichment, reverse email lookup.
IP: IP/network lookup, reverse IP.
Web and identity: website scraper, website contacts scraper, search intent lookup, skip tracing, job-change monitoring.

The full, current product list is in the catalog: app.1lookup.io/catalog. Per-product credit costs are on the Billing page in the dashboard.

Coverage, stated honestly

Coverage differs by product:

US and Canada are our strongest coverage across the phone products, and reverse phone/email/IP lookup and skip tracing are US-focused.
HLR, ported-number, and number-type lookups work internationally: they query live carrier networks. International phone spam/risk scoring also exists.
DNC/compliance checking is a US product.

We do not publish country counts or blanket accuracy percentages, because honest coverage varies by product and country. The reliable way to know whether 1Lookup fits your country and use case: run a sample of your own data on a trial. Volume buyer? The team will confirm coverage for your exact case before you commit: book a demo at ca

Question 2

Privacy and security

Accepted Answer

Your account's privacy in the chat

Support (including Jake, our AI agent) will never confirm or deny to anyone whether an email address has a 1Lookup account. Before any account details are shared in chat, we verify you with the email on the account plus the last 4 digits of the card on file. That is the most we will ever ask for: never a password, never a full card number, never a full API key.

If you paste a secret (an API key, a password) into any chat by accident, treat it as exposed: rotate the API key on the API Keys page or change the password.

Your data

We store your account details and your lookup history (inputs and results) so you can re-download results. Data is stored encrypted on AWS.
Want your data deleted? Write to us in the chat or at support@1lookup.io; deletion requests are honored, except records we must keep for legal and billing reasons.
We do not name the individual upstream sources behind products; data comes from licensed commercial sources and live network checks.

Acceptable use

1Lookup is for legitimate business contact and verification purposes. Using it to stalk, harass, or defraud people is against the terms and gets an account closed.

Question 3

How accurate are the results?

Accepted Answer

What a result means

A lookup is a point-in-time signal from live network, mailbox, and data checks, not a permanent fact:

A phone number can be active at lookup time and disconnected next week. Carriers recycle numbers constantly.
An email server can accept a verification today and bounce a real mail tomorrow. Some servers (catch-all domains, some corporate filters) accept everything during verification and sort it out later, which is how "deliverable" can still bounce.
Spam and risk scores are probabilities built from signals, not verdicts.
Reverse lookups return what our sources hold. For some numbers, emails, and IPs that is nothing, and "no data found" is a normal answer.

A result looked wrong?

One or two misses are expected with any validation provider, for the reasons above.
A pattern across real volume (many "valid" numbers disconnected, a big share of results empty) is something we want to see: write to us in the chat with the product you used and a few example inputs, and the team reviews it.
Credits charged on failed lookups: tell us in the chat; we can pull your recent lookups with per-row status and credits, and the team reviews any discrepancy.

Comparing against another provider

Different providers refresh different sources at different times, so disagreements between vendors are normal and do not by themselves mean either is broken. If the gap is large on real volume, send us examples.

Question 4

Batch uploads: process a CSV

Accepted Answer

How it works

Go to Batch Upload in the dashboard.
Upload your CSV, pick the product to run, and map the column.
The platform processes the file in chunks with live progress: processed, successful, failed, duplicates.
Download results from the batch page when it finishes, including filtered exports such as "valid only".

Files up to roughly 1 GB / 2 million rows are supported. Batch rows spend credits at the product's normal per-lookup cost, and duplicates inside a file are detected and not double-charged.

What is normal

Large batches take a while. "Processing" with the counters moving is healthy.
Some rows failing is normal (malformed numbers, empty cells); the failed count with reasons is in your results.

When to contact us

Write to us in the chat if a batch is stuck at the same count for a long time, failed outright, will not download, or spent credits that do not match the row counts. We can see your batch's live status on our side. Please do not re-upload a large file before checking with us: a re-uploaded file is a new job and can spend credits again, and we would rather fix the stuck job and review the credits with you.

Question 5

Troubleshooting common problems

Accepted Answer

A page won't load, or a lookup shows an error

Retry once; a one-off timeout can happen. If the same action fails repeatedly, tell us in the chat which page, what the error says word for word, and when it happened: repeated failures are something we fix on our side, not a cache problem on yours.

A lookup failed but credits were deducted

Ask in the chat: we can list your recent lookups with per-row status and the credits each one spent, and a team member reviews anything that looks wrong.

Where are my results?

Single lookups: on the page and in Lookup History.
Batch uploads: on the batch's own page once processing finishes.
A download button that does nothing: tell us which browser and the batch name.

Is there a phone number to call?

Support runs here in the chat and at support@1lookup.io. There is no support phone line. For sales conversations at volume, book a demo: cal.com/team/ml/1lookup.

"Is this legit?"

Usually asked after seeing the trial card hold: see "The free trial, and the card hold that looks like a charge". Short version: $0 is charged today, the pending line is a temporary hold, and cancellation is self-serve under Billing.

Want a human?

Say so in the chat any time: the conversation goes to a person with everything you already wrote, no gatekeeping. You can also email support@1lookup.io directly.

Question 6

Plans, pricing, and how credits work

Accepted Answer

Plans

Four self-serve plans: Starter ($99/month), Growth ($299/month), Professional ($799/month), and Enterprise ($1,999/month). Annual billing costs ten months' price for twelve months. Every paid plan starts with a 7-day free trial. The live plan comparison with included credits is on the Billing page in the app (the trial page itself offers Starter and Growth).

There is also a free plan with 25 credits per month, no card required, for use in the dashboard (API calls need a trial or paid plan). It keeps your API keys and lookup history saved.

How credits work

One shared pool of credits per account; every product draws from it.
Different products cost different credits per lookup. A basic phone validation costs less than a reverse lookup or a skip trace. The live per-product costs are on the Billing page in the dashboard (the credit costs card).
Plan credits refill each billing cycle. Rollover, purchased top-ups, and bonus credits live in separate buckets with their own expiry dates, all shown on your dashboard and billing pages.
Think credits were deducted wrongly? Ask in the chat: we can pull up your recent lookups with the exact credits spent on each, and a team member reviews any discrepancy.

Common questions

Pay-as-you-go? Plans are subscriptions; credit top-ups exist alongside a subscription. For volume beyond the listed plans, book a demo at cal.com/team/ml/1lookup.
Credits or tokens? Sam

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