Microsoft Excel Add-on Guide

The Similarweb Microsoft Excel Add-on (Updated June 2025) brings Similarweb’s digital intelligence directly into your spreadsheets. Use custom formulas to pull real-time web traffic, engagement, keyword, and geographic data—no code required.

Installation and Setup

The Similarweb Excel Add-in enables customers with API access to seamlessly pull traffic and engagement data directly into Microsoft Excel. This eliminates the need for manual API calls or technical expertise, allowing users to:

  • Retrieve data directly within Excel using simple formulas.
  • Automate updates in reports without needing additional scripts.
  • Combine Similarweb data with internal datasets for deeper insights.
  • Create custom metrics and aggregations on demand.

This guide walks through installation, setup, usage, and advanced features, ensuring you get the most value from the add-in.

Installation & Setup

Installing the Add-in

You can install the Similarweb Excel Add-in via:

Microsoft AppSource

  1. Open Excel, go to Insert > Get Add-ins. Or open Home > add-ins
  2. Search for Similarweb.
  3. Click Add, then confirm installation.
  4. Alternatively you can visit the Microsoft Appsource product page and install the Add-in from there.

Option 2: From the Sheets

  1. Open any sheet
  2. Go to Extensions > Add-ons > Get add-ons
  3. Search for Similarweb and install

Authenticate with Your API Key

  1. Go to your Account Settings > REST API
  2. Copy your API key
  3. In the Similarweb add-on sidebar, paste your key
  4. Click Save to activate


Discover Available Functions

To explore all supported datasets and functions, type this formula into any cell:

=SIMILARWEB_GET_ALL_FUNCTIONS()

This will return a full list of grouped formulas—covering traffic, geography, keywords, rankings, marketing channels, and more.


📘

Click on "fx" next to any function in the output list to open the Formula Builder and discover its parameters and rules, including accepted date formats, geo codes, metric options, and required fields.


Retrieving Data in to Excel

Instead of querying individual metrics, the new structure uses 10 grouped functions—each one supporting multiple metrics via a single call.

Example: Traffic & Engagement

=SIMILARWEB.WEBSITES_TRAFFIC_AND_ENGAGEMENT("cnn.com","2025-01","2025-04","monthly","total","us","visits,bounce_rate,page_views,average_visit_duration,pages_per_visit,unique_visitors")

This retrieves traffic and engagement data for CNN in the US from January to April 2025.

💡

You can request one metric, several, or all available by editing the metrics field.

Parameter Guide

ParameterDescription
domain_nameWebsite domain (e.g., "cnn.com")
start_date / end_dateFormat: "YYYY-MM" or "YYYY-MM-DD"
granularity"daily", "weekly", "monthly" (default: monthly)
web_source"total", "desktop", "mobile_web"
countryISO code (e.g., "us", "gb", "ww")
metricsComma-separated list: visits, bouncerate, page_views, average_visit_duration, pages_per_visit, unique_visitors. Leave blank to pull all. (recommended: specify desired metrics to future-proof your reports)_
mtdTRUE/FALSE — include month-to-date values
main_domain_onlyTRUE to exclude subdomains
aggregationAggregate over the date range: SUM, AVG, MIN, MAX, MEDIAN, FIRST
return_values_onlyTRUE to return only the raw values (no headers or dates)

Default Behavior

  • If no dates are provided → latest available data will be used for daily and monthly granularity. Weekly requires exact start and end dates.
  • If metrics is not specified → all available metrics will be returned.

💡

We highly recommend specifying only the metrics you need, as more will be added over time.

Advanced Examples

These examples demonstrate how to use Similarweb formulas with specific parameters to pull the exact insights you need. In the examples below, the last field in the formula will be the relevant field.

1. Choose Specific Metrics

Use case: Pull only the traffic and engagement metrics you need, rather than returning the full default set.

Relevant field: metrics

Example:

=SIMILARWEB.WEBSITES_TRAFFIC_AND_ENGAGEMENT("cnn.com","2025-01","2025-04","monthly","total","us","visits,bounce_rate,page_views,average_visit_duration,pages_per_visit,unique_visitors")

2. Aggregate Results Across Time Range

Use case: Summarize multiple months into a single value using median (or other aggregations like SUM, AVG).

Relevant field: aggregation - Use "MEDIAN", "SUM", etc., to condense the time period

Example:

=SIMILARWEB.WEBSITES_TRAFFIC_AND_ENGAGEMENT("cnn.com","2025-01","2025-04","monthly","total","us","visits,bounce_rate,page_views,average_visit_duration,pages_per_visit",,,,"MEDIAN")

3. Values Only (No Headers)

Use case: Output only the numeric results - no column labels or date headers. Ideal for embedding into existing reports.

Relevant field: return_values_only - Set to TRUE() to exclude labels and dates

Example:

=SIMILARWEB.WEBSITES_TRAFFIC_AND_ENGAGEMENT("cnn.com","2025-01","2025-04","monthly","total","us","visits,bounce_rate,page_views,average_visit_duration,pages_per_visit",,,,"SUM",TRUE())

4. Limit Results (Top Geography)

Use case: Pull the top countries driving traffic, limited to a specific number of rows.

Formula used: SIMILARWEB_WEBSITES_TOP_GEOGRAPHY

Relevant field: limit - Caps the number of rows returned (e.g., 10)

Example:

=SIMILARWEB.WEBSITES_TOP_GEOGRAPHY("cnn.com","2025-01","2025-04","monthly","total","share,visits,rank,average_visit_duration,pages_per_visit,bounce_rate",,"sum",,10)

5. Rolling Dates for Freshest Data

Use case: Get the latest available daily or monthly data without manually setting dates. Leave start_date and end_date blank.

Relevant field: start_date and end_date - Date fields need to be left blank to get the latest available data. If you set granularity to 'monthly' you will get 3 months of data. If you set granularity to 'daily' you will get 28 days of data.

Daily example:

=SIMILARWEB.WEBSITES_TRAFFIC_AND_ENGAGEMENT("cnn.com",,,,"daily","total","us","visits,bounce_rate,page_views,average_visit_duration,pages_per_visit,unique_visitors")

Monthly example:

=SIMILARWEB.WEBSITES_TRAFFIC_AND_ENGAGEMENT("cnn.com",,,,"monthly","total","us","visits,bounce_rate,page_views,average_visit_duration,pages_per_visit,unique_visitors")

You can also:

  • Use Freeze API Calls to prevent accidental usage
  • Or delete your key from the sidebar and click Save

Troubleshooting & Errors

ErrorCause
# ERROR! (no response)Invalid API key or domain
Data Not Found (404)Unsupported domain or country
Invalid CountryWrong country code
Blank CellPossibly return_values_only = TRUE with no data returned

Advanced Features

Aggregation

Summarize your results with functions like:

SUM, AVG, MIN, MAX, MEDIAN, FIRST

Example:

=SIMILARWEB.WEBSITES_TRAFFIC_AND_ENGAGEMENT("cnn.com","2025-01","2025-03","monthly","total","us","visits,page_views",,,,"AVG")

Return Values Only

Omit headers and dates:

=SIMILARWEB.WEBSITES_TRAFFIC_AND_ENGAGEMENT("cnn.com","2025-01","2025-04","monthly","total","us","visits",,,,"SUM",TRUE())

FAQ

What's the best way to get started?
Run =SIMILARWEB.GET_ALL_FUNCTIONS() to explore all supported formulas. Click on any function name to preview its parameters.

What metrics are available?
Metrics vary by formula group. For traffic and engagement, you can access: visits, bounce_rate, page_views, average_visit_duration, pages_per_visit, and unique_visitors.

Why should I specify metrics?
More metrics will be added over time. Specifying the ones you need ensures consistent output and helps future-proof your Sheets.

What happens if I don't input dates?
You'll receive the latest available daily or monthly data by default. Weekly granularity requires start and end dates.

Can I limit the number of rows returned?
Yes—some functions like SIMILARWEB_WEBSITES_TOP_GEOGRAPHY support a limit parameter.

Can I schedule data refreshes?
Yes! Use Excel capabilities Script to schedule refreshes based on your reporting needs.

Is the add-on free?
Yes, it's free for all Similarweb customers with API access.

How is usage billed?
Each API call consumes credits according to your subscription plan.