How Many Leads Do You Need to Buy to Get a Send List of 5,000?
Leads to buy equals the send list you need divided by the share that survives cleaning and verification: if 80 percent survive, you need 6,250 leads to send to 5,000 people. The 80 is an example, not a benchmark. Your list's real number comes from a sample, and you can get it before you buy the rest.
The formula
leads to buy = send list needed / surviving share
| Surviving share (example) | Leads for a 5,000 send list |
|---|---|
| 90% | 5,556 |
| 80% | 6,250 |
| 70% | 7,143 |
| 60% | 8,334 |
These are arithmetic, not forecasts. They show how fast the number you have to buy grows as quality falls.
Step 1: get a sample from the vendor
Ask the vendor for a random sample of 100 rows, or buy the smallest tier and sample from it. Do not accept a hand-picked demo. See questions to ask a B2B data vendor for what to ask.
Step 2: verify the sample
Run the 100 addresses through the verify page. The first 100 checks are free with a Google sign-in, no card. Count the valid rows: that is your surviving share. The purchased email list checker is a free first look at a list you already have.
Step 3: allow for the margin of error
A sample of 100 is a rough measure. At that size the 95 percent margin is up to about 10 points either way, so a result of 80 valid could mean 70 to 90 percent on the full list. Plan with the low end: if you saw 80, work out the number to buy at 70.
Step 4: decide what counts as sendable
Decide before you do the sum:
- Valid only. The safe rule: only valid addresses go in the main send.
- Valid plus some risky. Hold risky rows for a small second batch. See catch-all emails: what to do.
Step 5: add the cost of checking
You pay to verify every row you buy, not only the ones that survive. At 6,250 rows, a one-time pack of 10,000 checks at $15 covers it, and Starter at $9 a month covers 2,500 emails. Cost per verified contact turns it into a per-contact number.
What this will not tell you
It does not tell you whether the contacts are the right buyers, or how many will reply. It only tells you how many addresses you will be able to send to without bouncing.
Next step
Run 100 free checks on the vendor's sample before you buy the full list. See pricing for packs from $15 per 10,000 checks, Starter at $9 a month and Pro at $39 a month.
Common questions
How many leads should I buy to send to 5,000 people?
Divide 5,000 by the share of the list that survives cleaning and verification. If 80 percent survive, you need 6,250. The 80 is an example, not a benchmark: measure your own with a sample.
How do I measure the share that survives?
Take a random sample of 100 addresses from the vendor's list and verify them. Count the valid ones and divide by 100. That is your estimate, and it is rough.
How accurate is a 100-address sample?
It has a wide margin of error. At 100 rows the 95 percent margin is up to about plus or minus 10 points, so 80 valid could mean anywhere from roughly 70 to 90 percent on the full list. Plan with the low end.
Do risky addresses count as sendable?
Only if you decide to send to them. Many senders count only valid addresses in the main send and hold risky ones for a small batch. Decide your rule before you do the sum.
Can I ask the vendor to replace bad leads?
Some vendors offer replacements or credits for bounces. Read the terms and test a sample before you buy, because a promise to replace is less useful than a clean list.
Check your list before you send
Real mailbox checks over SMTP, and nothing is sent to the address. Sign in with Google and your first 100 email checks are free, no card. Plans for bigger lists are on the pricing page.