SendLockMissing attachment
No file attachedHere is the signed contract, attached for your records.
- Says “attached” but no file is attached.
Undo any email.
SendLock holds every Gmail send for as long as you choose.
Stop it, fix it, send it again.
Add to Chrome. It’s free
Free for individuals, forever. No credit card.
On your phone? SendLock runs in Chrome on a computer. Email yourself the link.
Live demo
Try it. Press Send, then take it back.
A
SendLock
Send delay
30sec
Time to stop or edit an email after you hit Send. In the extension, any time up to 60 minutes.
Smart flags
Sarah ChenRe: Proposal - Looks good. Send John the pricing when it is ready10:42 AM
John MillerPricing? - Any update on the numbers for Q4? We decide on Friday9:15 AM
FinanceQ4 price list, final - Use this one, not the September draftNov 10
Dana OrtizLunch Thursday? - There is a new place on Water StreetNov 9
Priya ShahContract redlines - Two small changes on page 4, otherwise fineNov 9
Marcus LeeOffsite agenda - Draft attached, tell me what is missingNov 6
CalendarInvitation: Q4 review - Thursday 2pm, Conference room BNov 6
Li WeiThanks for yesterday - Great to meet the team. Next steps belowNov 5
AccountsInvoice 1042 - Paid in full, receipt enclosedNov 4
Sam RiveraIntro: Sam and Alex - Connecting you two as promisedNov 3
New Message
- Says “attached” but no file is attached.
- “Thursday, November 20” isn’t a Thursday.
- Greeting says “Sarah” but this goes to John Miller.
A working copy of SendLock, running in this page. It holds for 30 seconds here; SendLock’s default is 15. Nothing you type is sent or saved.
Gmail’s Undo Send against SendLock
Gmail gives you 30 seconds. SendLock gives you 60 minutes.
Gmail’s own Undo Send is a small pop-up that lasts 5 to 30 seconds. Most mistakes are noticed after it has gone.
Gmail Undo Send 30 seconds at most
SendLock up to 60 minutes
Drawn to scale. The black sliver on the left is Gmail.
| Feature | Gmail Undo Send | SendLock |
|---|---|---|
| Longest window | 30 seconds | 60 minutes |
| Where the email waits | Behind a pop-up in the corner of the screen | In a SendLock folder in Gmail, with a countdown bar |
| Pause the clock | No | Yes |
| Checks the greeting name and the weekday | No | Yes, with Smart Flags |
Smart Flags
Mistakes caught while you write.
SendLock reads the email you are writing, inside your browser, and warns you in the SendLock bar at the top of Gmail. Six checks are on from the start.
Leftover placeholder
To: Priya ShahHi [NAME], thanks for your time on the call today.
- Found placeholder: [NAME].
Wrong weekday
Sent in 2026Let’s meet on Tuesday, November 12 at 2 pm.
- “Tuesday, November 12” isn’t a Tuesday.
Wrong name
To: John MillerHi Sarah, great meeting you yesterday.
- Greeting says “Sarah” but this goes to John Miller.
Mistyped address
Todana.ortiz@gmial.com
- dana.ortiz@gmial.com: did you mean gmail.com?
Outside recipient
Tomaria@yourfirm.com, li@yourfirm.com, sam@otherco.com
- sam@otherco.com is outside yourfirm.com.
Two more you can switch on: a reply that goes to several people, and an email to a group of three or more. Every flag has its own switch.
How it works
1-minute install, lifetime protection.
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1Add SendLock to Chrome
Free, and it takes a minute.
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2Press Send like always
Nothing new to learn.
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SendLock0:15
3Every send waits for you
Stop it, fix it, send it again.
Privacy and security
Your emails stay in Gmail.
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Runs in Chrome
SendLock works right inside Gmail, on your own computer.
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Held in your Gmail
Waiting emails never leave your account.
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Tested by TAC Security
Independently tested to Google’s security standard.
Pricing
Free for individuals. $48 a year per person for teams.
SendLock
$0 for individuals
Free forever. No credit card.
- A send delay from 15 seconds to 60 minutes
- Stop, edit and resend any held email
- All eight Smart Flags
- Pause, send now and Outbox mode
SendLock Team
$48 per person, per year
Billed once a year. 5 people or more.
- A minimum send delay for the whole team
- Locked on: team members cannot switch it off
- You choose whether members may use Send now
- One admin dashboard to add people and set the rules
How Team works
Protect every send in your company.
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1Sign in with your company email
Go to team.sendlock.com and sign in with Google. The team is for people on your company’s email domain. Personal addresses such as gmail.com are not accepted.
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2Name your team and pay
Enter a team name and the number of people, then pay on Stripe’s checkout page. Stripe accepts cards, Apple Pay and Link, including pay by bank through Link.
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3Add people and set the rules
In the dashboard, admins add people and set the minimum send delay for everyone. A new team starts at 15 seconds, with Send now allowed. A team can have more than one admin; the buyer is the owner.
- Add seats any time. The cost is shown before you confirm, and you pay only for the rest of the paid year.
- Billing stays with the owner. The owner manages the card, invoices and cancellation on Stripe’s billing page, reached from the dashboard.
- Cancel without losing cover. A cancelled team keeps its rules until the end of the paid year.
Questions
How is SendLock different from Gmail’s Undo Send?
Gmail’s Undo Send is a pop-up that lasts 5 to 30 seconds. SendLock holds the email before it leaves your account for a delay you choose, from 15 seconds to 60 minutes. During that time you can stop it, reopen it, fix it and send it again.
Does SendLock read or store my emails?
SendLock does not send the content of your emails to our servers and does not store it. To hold an email and to check it for mistakes, the extension works with your draft inside your own browser and your own Gmail account.
What happens if I do nothing during the delay?
The email sends on its own when the delay ends. No extra clicks.
What are Smart Flags?
Checks that run while you write and when you press Send. They warn you about a missing attachment, a leftover placeholder, a weekday that does not match its date, a greeting with the wrong name, a mistyped address, and an outside recipient mixed in with colleagues. You can switch each one on or off.
Does it work on every email I send?
Yes, for the Google account you signed in to SendLock with: new emails and replies sent from Gmail in Chrome on a computer. If you use a second Google account in the same browser, emails from that account are sent normally, and SendLock tells you so. It does not cover the Gmail mobile apps.
Is SendLock really free?
Yes. SendLock is free for individuals, forever, with no credit card.
Is there a version for companies?
Yes. SendLock Team is $48.00 per person per year, billed once a year, for 5 people or more. Admins set a minimum send delay for the whole team, and team members cannot switch it off. Get it at team.sendlock.com.
Send with a second chance.
Add SendLock to Chrome and the next email you regret will still be yours to stop.
Add to Chrome. It’s free