New

Domain Burn Alerts: free detection for SmartLead and Instantly. Domain Burn Alerts: free for SmartLead & Instantly

Check your domains

Scale Your Outreach: Using Bulk Cold Email the Right Way

Robotic arm placing emails onto a conveyor belt with gears

You love the cold emailing concept, maybe you’ve also sent a few. Now, you want to scale up, send more bulk cold emails, get more leads, more replies…but you’re not sure how. Don’t worry, you’re in the correct corner of the Internet. We’ll break down everything, including setup, bulk cold email sending limits, segmenting lead […]

13 Cold Email Mistakes To Avoid in 2026

Open email with a warning triangle and paper planes scattering away

Introduction Everyone makes cold email mistakes. That’s not the problem. The problem is making the same ones twice. Especially when the cold email landscape in 2026 is less forgiving than ever. Google and Yahoo’s bulk sender requirements have raised the floor. Inboxes are smarter, prospects are colder, and yet, cold email is still one of […]

Email Warmup Made Easy for Cold Email Success

Paper airplanes in formation with a red email leading the way

You’ve got your lead list, verified it, ensured your copy is perfect, and everything is in order. But your cold email still gets no replies. This is probably because it ended up in the spam folder. Now, there is no way for you to know, but there are a few reasons this could happen. One […]

What Is a Good Reply Rate for Cold Email? (2025 Industry Benchmarks)

Donut chart and bar chart with a benchmark line and reply bubbles

You’ve done your technical set-up, cleaned up, verified your lead list, and ensured your copy is perfect. You hit send…and then nothing. Sounds familiar? It’s the sad reality of most cold emailers. So, if you find yourself asking, “What is a good reply rate for cold emails?”, you’re at the right place. We’ll break down […]

Cold Email Deliverability Infrastructure for Agencies

Building with shields, domain cards, and an upward trend chart

Cold Email is your bread and butter. We understand that because it’s ours too. At the end of the day, every booked meeting is additional revenue and directly impacts client retention. You spend money creating campaigns and building lead lists to achieve a consistent flow of replies. That’s what your clients trust you to do. […]

What is Aerosend?

Server stack with interlocking gears, a shield, and a trend chart

We’re an inbox provider built for cold emails.  To make cold email successful, you need to send very few emails from 1 domain (60-75 emails/day/domain). To scale automated outreach, you need multiple domains and inboxes working together. This helps providers think you are not doing mass outreach, and your emails will land in the inbox. […]

What are Gmail’s Daily Email Sending Limits per day in 2026?

Speedometer at the redline zone with a counter display and stop sign

Gmail is the most popular provider. But should you use it for cold email? If you’ve found yourself in the midst of the “you have reached a limit for sending mail Gmail” notification, you’ve likely reached the Gmail sending limit. Gmail sending limits are 2000 on paper. For cold emailers, it’s 25 per inbox. A […]

Best Time to Send Email Blast: Does It Even Matter?

Clock face with highlighted hours, a calendar with pins, and a timeline

Most people ask about the send time after they’ve done the hard work. Copy is ready, offer is dialed in, list is built. It feels like the last piece of the puzzle. It isn’t. Send time is one of the weakest levers in cold email. Your offer, your targeting, and your technical setup will determine […]

Coming Soon
SPF/DKIM/DMARC Checker Soon

Validate your email authentication

Blacklist Checker Soon

Check if your domain or IP is blacklisted

Email Spam Checker Soon

Test if your email lands in spam

How to Get Your Instantly API Key
Step 1 : Log in to Your Instantly Account
Go to https://app.instantly.ai/auth/login and log in to your account
Step 2 : Navigate to Settings

Click on your profile icon in the bottom-left corner, then select “Settings” from the dropdown menu.

Step 3 : Select Integration

In the Integrations page, click on the “API Keys” tab in the left sidebar.

Step 4 : Get Your API Key with all:read Scope

If you already have an API key with the all:read scope, you can use that key.


If not, click the “Create API Key” button, select the all:read scope, and make sure to save your new API key somewhere safe.

How to Get Your Smart Lead API Key
Step 1 : Log in to Your Smart Lead Account
Go to https://app.smartlead.ai/login account and log in to your account
Step 2 : Navigate to Settings

Click on the “Settings” option in the top right corner profile icon.

Step 3 : Select API Integration

In the Settings page, under your profile picture, you can see the SmartLead API Key.

Step 4 : Generate Your API Key

If you already have an API key displayed, you can use that key. If not, click the “Generate API Key” button to create a new one.