13 Free OSINT Tools for Adding Context in Person-of-Interest Investigations


The digital landscape continues to change faster than the technologies used for intelligence gathering. The sheer amount of information generated daily poses a significant challenge in terms of resources. Meanwhile, the rapid evolution of digital communication platforms creates challenges of its own. Law enforcement agencies, private companies, and security consultancies alike suffer from shortage of personnel, time, and budget to run comprehensive investigations that could match the scale of their task.

Luckily, open-source intelligence (OSINT) tools grow more powerful with each passing day and month. Even more luckily, many of these tools are free to the public. Below, you will find our list of the 12 best free OSINT tools, which are specifically valuable for person-of-interest investigations.

Table of Contents

A Brief History of Persons-of-Interest and OSINT Tools

Before we dive into the free OSINT tools below, it’s important to understand what exactly a person-of-interest is. Not only this but also how current investigations face challenges while using OSINT tools to identify POIs.

Person-of-Interest (POI) – Definition

Person-of-interest is a term originally widely used by law enforcement and intelligence officials to identify someone linked to and/or in possession of information pertinent to an ongoing criminal investigation. As the specialisation of online investigations grew beyond the military and law enforcement into private sectors, the term has been adopted by trained practitioners (for example cyber security experts or open-source intelligence analysts) conducting specialised investigations of persons. The term has no legal implications. 

Nowadays, persons suspected of illicit activities are tech-savvy and resourceful. They move throughout the digital landscape with access to a much broader set of tools to conceal their identity and activity online. As a result, it has become much easier for persons-of-interest (POI) in investigations to slip under the radar of law enforcement authorities, prosecutors, and even investigative journalists. Those searching through open-source intelligence must be particularly vigilant in exploring every angle. Furthermore, one important aspect of POI investigations which can sway the conclusions of an OSINT report is context.

Context Awareness in OSINT Investigations

Peter Cochrane, an international sought-after advisor and consultant with over 40 years of technology and operational experience, summarised the necessity for context awareness in interpreting intel on the topic of modern hybrid warfare:

“[…] intelligence systems have to be responsive to long-term monitoring and engage in deep observation and  analysis of the situation. The data must be applied to the wider context to reveal unknowns and contingencies.”

This, suggests Cochrane, calls for minimization conditions that foster errors. For example, these could be focusing on narrow situation modelling or not factoring in human and machine cognitive bias.

Therefore, an efficient and conclusive strategy for OSINT investigations of POIs combines automated cross-media intelligence gathering workflows with open-source tools developed to target very specific information gaps.

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13 Free OSINT Tools for Persons-of-Interest Investigations

We asked our in-house OSINT analysts to share their favourite and freely available resources for performing a deep-dive investigations meant to uncover the digital footprint of POIs. The following open-source investigative tools are powerful but come with limitations. To get the most out of your investigation, we recommend using these tools alongside a media mining system. To learn more about The Media Mining System we have created here at HENSOLDT Analytics, read here.

    1. BuiltWith Technology Lookup

      BuiltWith covers 60,409+ internet technologies, which include analytics, advertising, hosting, CMS and many more. By entering a URL in the search bar, you can see the elements a website has been built with and what tools it uses. With BuiltWith.com Technology, data is accessible as far back as January 2000.

      tool to see what websites have been built with

    2. Have I Been Pwned

      Have I Been Pwned enables investigators to quickly check whether their POI’s email address or phone number have been in any past data breaches.

      tool to see if email address or phone number has been in breached

    3. Instant Street View

      Instant Street View allows users to instantly fetch any address or place from the Google Street View. Users find the interface to be easier to navigate than attempting to do the same in Google Maps.

      tool to see Google Street View for an address

    4. MapChecking

      MapChecking helps you estimate and fact-check the maximum number of people standing in a given area. Set the parameter for the area you wish to measure, choose how populated it should be, and the tool will give you an estimate number of people.

      tool to count how many people are in an area

    5. Pushshift’s Reddit Search Application

      According to the creator of the Reddit Search tool, this application allows for cross-post and comment searches, as well as specific user or subreddit searches. In addition, OSINT analysts can aggregate data to identify trends. As of 2022, reddit is blocked in India, Indonesia, Russia, and China.

      Search tool for reddit users and subreddits

    6. Radio Garden

      Radio Garden allows you to browse radio stations by rotating the 3D globe. It doesn’t map all existing stations, but it’s a helpful tool to add local reference sources to your report.

      website to listen to radio stations around the world

    7. Snap Map

      Snap Map ran by Snapchat aggregates a selection of public snapchat media uploaded by its users. The videos and images can be grouped by geolocation or public events.

      heat map of Snapchat content

    8. Strava

      Strava’s Global Heatmap focuses specifically on monitoring and visualising ‘heat’ made by aggregated, public activities over the last year. The public data shared by athletes from around the world identifies sport activity hotspots. The tool is also used by athletes to identify their next routes.

      heatmap of Strava user activities

    9. The Ventusky Web App

      For those investigating events from all angles, weather conditions can play an important part in explaining the context of a POI’s movements. The Ventusky app provides interesting food for thought. The tool clearly displays meteorological data from around the world and allows users to monitor weather developments for any place on Earth at different times. Depending on data sources, some of the data visualisations date back decades.
      website to check weather conditions

    10. The Wayback Machine

      The Wayback Machine captures websites as they are and stores the screenshot, URL changes, and the timeline of changes for reference. The Wayback Machine is a crucial resource in the fight against disinformation as it records content meant to be short-lived.

      website to check what websites used to look like

    11. TinEye

      TinEye’s computer vision, image recognition and reverse image search matches your upload image with its duplicates online. It’s a useful tool for verifying users’ activity or connecting images to stock images databases.

      website to do a reverse image search that is not Google

    12. Whois

      Whois lists domain information allowing users to check the person owning the website you are looking at. The information provided to the Whois registry is voluntarily provided by the domain owners and unverified by the service.

      Tool to see what domains are available and who owns them

    13. Verify-Email.org

      A useful email verification tool, Verify-Email connects to the mail server of an email address and checks whether the mailbox exists or not. This is particularly helpful for eliminating false lines of communications.

      tool to check if an email address is real or not

Configuring our Media Mining System

As mentioned above, free OSINT tools can only go so far. Using a proper tool as the basis for your investigation with the help of the free tools listed above will yield the best results.

The HENSOLDT Analytics system fuses a range of Neuronal Language Processing (NLP) and artificial intelligence (AI) together into one comprehensive platform. Our Media Mining System enables users to schedule and to automatically collect, index, systematise, and visualise open-source information from TV, radio, internet, RSS feeds, and social media 24/7.

The result is a robust, fully configurable platform able to extract actionable insights for situational awareness reports on very specific topics and events. Think of the Media Mining System as a wide net cast into the sea of information to pick out only the relevant pieces of intel – pieces that the system has been specifically calibrated to find.

Calibrating the Media Mining System’s Profiles

The Media Mining System comes with a prefabricated set of Profiles (or Named Entities, NE’s) covering persons, organizations and locations. These can be extended by end-users with proper permissions and training. Further classes of profiles, such as natural disasters, diseases or financial entities can easily be created using the profile-editor. Profiles form the basic building blocks for the complex construction of hierarchical interconnection, the Ontologies. Profiles capture the different ways an entity can be referred to in the real-world and across different languages simultaneously.

Please refer to the user guide for a step-by-step instructions in creating profiles. If you had not purchased the Media Mining System but you are interested in hearing more about it, contact us now to schedule a live demo with our team.

Once the Media Mining System identifies key profiles, hashtags, influencers and platforms for the searched query, the open-source intelligence analysts can generate a report summarising key findings.

Now, equipped with the first detailed analysis, the investigator will continue with their deep web search to gather additional open-source information for a complete person-of-interest report.

HENSOLDT Analytics
HENSOLDT Analytics

HENSOLDT Analytics is a global leading provider of Open Source Intelligence (OSINT) systems and Natural Language Processing technologies, such as Automatic Speech Recognition, which are key elements for media monitoring and analysis.