Email list daily batch splitter: split a list into growing daily sends
In short: Upload a list, set the first day's size, the daily growth and the cap, and every address gets a send day, with domains mixed in each day. Download one file with a send-day column. Limit: It plans which address goes on which day; it does not send or warm up anything.
Upload a list, set how many to send on day one, how much the batch grows each day and the most you will send in a day. Every address gets a send day, with domains mixed through each day, and optional dates that skip weekends. Download the list with a send-day column and the plan as a table.
Price: this tool is free. Checking a whole email list is from $9/mo, and the first 100 checks are free with Google, no card. Check your list free nowSee pricing
Year-month-day.
Sample result
12 example addresses go out over 4 days: 2, 3, 5 and 2, from Thursday 2026-11-19.
- Send days
- 4
- Day 1
- 2
- Cap
- 6
What this means for you
Each day mixes the domains, and the dates skip the weekend.
- First day, growth and cap
- Domains mixed each day
- Optional dates, no weekends
- List with a send day
- Batches
- Ramp
- Lead list
By SimpleVerifier Team · Last updated · Runs in your browser; nothing you paste is sent to us
Batches planned, now check the list before day one.
- Download the list with its send-day column, or use the check button under the result.
- Upload or paste it at /verify. Every address gets a live mailbox check, and the first 100 email checks are free with a Google sign-in, no card.
How do I split an email list into daily batches?
- Upload the list as a CSV or .xlsx, or paste the cells with the header row first. It needs a column of email addresses.
- Set the first day's size, the daily growth in percent and the daily cap. Add a start date if you want dates.
- Press Make the batches and read the plan: one row per day with its size and date.
- Download the list with a send-day column, load each day into your sender, and check the list before day one.
Example
- You enter
- Example list of 12 addresses on three domains, 2 on day one, growing 50 percent a day to a cap of 6, starting Thursday 2026-11-19 with weekends skipped.
- You get
- 12 addresses over 4 days: 2, 3, 5 and 2. The days fall on 2026-11-19, 2026-11-20, 2026-11-23 and 2026-11-24.
- Limits
- Runs in your browser. It plans which address goes on which day and does not send or warm up anything.
How are the day sizes set?
Day one is the number you set. Each day after it grows by the percent you set, rounded up and by at least one, until it reaches the cap, then stays at the cap until the list is used up. With 0 percent growth every day is the same size.
The tool plans sizes only. It does not know your sender's limits, so set the cap to what your inboxes can send; the email sending limits calculator helps with that.
How are domains mixed?
Addresses are placed so each domain is spread evenly across the whole list, which keeps any one day from being mostly one company or one provider. A domain with very many addresses still has the most left over for the last days. For a gap between sends to one domain, use the same-domain send spacer.
Does this warm up a mailbox?
No. It splits a list. For the ramp of a new mailbox or IP, see the email warm-up calculator and the IP warm-up schedule calculator, and read the email warm-up schedule. A list with bounces ruins a ramp, so check it first.
Who uses this tool, and for what?
- Cold emailers
- Plan a ramp from 50 a day up to your inbox limit.
- Newsletter owners
- Re-introduce an old list in batches rather than one big send.
- Agencies
- Give each day's batch to a sender with a clear count and date.
What can’t this tool tell you?
- It plans which address goes on which day; it does not send or warm up anything.
- It does not know your sender's limits, so set the cap yourself.
- Dates skip weekends only; holidays are not known.
- A domain with a large share of the list still ends up in the last days.
Common questions
- What if a row has no address?
- It gets no send day and stays in the file with a blank send day.
- Can I skip weekends?
- Yes. Enter a start date and tick the box; the dates then skip Saturdays and Sundays.
- Does it send anything?
- No. It only plans which address goes on which day.
- Why does the last day have fewer addresses?
- It holds whatever is left after the full-size days.
- Can it keep the original row order?
- The download keeps your row order and adds the send day to each row.
- Is my list uploaded anywhere?
- No. The list is read in your browser.
A tidy list can still be full of dead addresses.
Extracting, deduplicating and syntax checks all work on the text of an address. None of them can tell whether the mailbox exists. Only the server that hosts it can answer that, through an SMTP check, and that is what the paid product does.
- Upload the cleaned file as it is: CSVs up to 100,000 rows
- A real SMTP mailbox check on every row, with catch-all detection
- Small list? Starter at $9/mo covers 2,500 emails a month, cancel anytime
Plans from $9 a month, cancel anytime, no contract. Sign in with Google and your first 100 email checks are free, no card. The free tools stay free either way.