Filter CSV rows by date: keep subscribers who signed up before, after or between dates
In short: Upload a list, pick the date column and a date. Mixed styles such as 2026-03-14, 14/03/2026 and Mar 14, 2026 are read, and unreadable dates are set aside, not guessed. Limit: It does not read the clock, so cut-off dates are typed in.
Upload a CSV or .xlsx file, or paste it with a header row. Pick the date column and choose before a date, on or after a date, or between two dates. Mixed styles such as 2026-03-14, 14/03/2026 and Mar 14, 2026 are read. You download the rows kept and the rest, with rows whose date is blank or unreadable set apart.
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
Sample result
Five example rows kept on or after 2026-01-01 give 2 rows, 2 outside the range and 1 unreadable date set aside.
- Rows kept
- 2
- Outside the range
- 2
- Order read as
- Day first
What this means for you
A recent date does not show that a mailbox works; a check shows which addresses exist.
- Before, after or between
- Mixed date styles
- Day or month first
- Unreadable set aside
- Date
- CSV
- Filter
By SimpleVerifier Team · Last updated · Runs in your browser; nothing you paste is sent to us
Filtered by date? Check the addresses you kept before the send.
- Download the rows kept, or use the check button under the result, which carries their addresses across.
- 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 filter a CSV by date?
- Upload the file as a CSV or .xlsx, or paste the cells with the header row first.
- Pick the date column and choose before, on or after, or between.
- Choose the date or dates, and the day and month order if the list is mixed.
- Check the counts and download the rows kept and the other rows.
Example
- You enter
- Five rows with a Signed up column of 2025-11-02, 14/03/2026, 9 Jan 2024, 2026-06-30 and not recorded, kept on or after 2026-01-01.
- You get
- 2 rows kept (14/03/2026, read as day first because 14 cannot be a month, and 2026-06-30). 2 are outside the range (2025-11-02 and 9 Jan 2024) and 1 cannot be read (not recorded), so it is set aside, not guessed.
- Limits
- Runs in your browser; nothing is uploaded. It does not read the clock, so the cut-off is a date you type.
When does a date filter help a list?
Old addresses go bad: people change jobs and abandon inboxes. A list sorted by sign-up date shows which part is oldest, so you can check or retire it first. A filter for after a date keeps the recent signups. A range keeps one campaign's signups or one month's imports.
For a policy on when to stop mailing the oldest contacts, read how to write a sunset policy.
Which date styles are read?
It reads 2026-03-14, 14/03/2026, 03/14/2026, 14.3.2026, 14 Mar 2026, March 14th 2026 and Mar 14, 2026. A time after the date is ignored, and a two-digit year is read as 20yy. A cut-off day is included in on or after and in between, and excluded from before.
A date such as 03/04/2026 could be 3 April or 4 March. If any date in the list has a first number above 12, or a second above 12, the order is worked out for the whole column. Otherwise month first is assumed and you are told; choose the order yourself to override it.
What does it not do?
It does not know today's date, so you type the cut-off. A date that cannot be read, or a blank, is not guessed: those rows are counted and downloaded with the rows outside the range. To rewrite a messy date column into one style first, use the CSV date format converter; to find contacts who stopped engaging, use the inactive subscriber finder.
Who uses this tool, and for what?
- Email marketers
- Split a list into recent signups and the oldest part to check first.
- Cold emailers
- Keep leads exported after a given date.
- Analysts
- Pull one campaign's or one month's rows out of a large export.
What can’t this tool tell you?
- It does not read the clock, so cut-off dates are typed in.
- Dates with only a month and year, or written in other languages, are not read and are set aside.
- An all-number date with day and month both 12 or below can be ambiguous; the order is assumed or chosen.
- Only the first sheet of a workbook is read.
Common questions
- Is the cut-off day included?
- In on or after and in between, yes. In before, no: before 2026-01-01 keeps 31 December 2025 and earlier.
- Can it read dates with a time?
- Yes. A time after the date, such as 2026-01-01 14:30, is ignored and only the day is compared.
- What if the day and month order is unclear?
- If the list settles it, the tool uses that. If not, month first is assumed and you are warned, and you can choose day first or month first.
- What happens to rows with no date?
- They are counted as blank or unreadable and download with the rows outside the range, never silently dropped.
- Can I filter by the age of a date, such as older than 90 days?
- Not directly, because the tool does not read the clock. Type the date 90 days ago as the cut-off.
- Is my file uploaded?
- No. The file is read in your browser and goes nowhere.
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.