Literature Map Tools Face-Off: Connected Papers vs Litmaps for PhD Research [2025]

During my time working with PhD research, I have seen many students struggle with what feels like an impossible task: making sense of the vast amount of literature published in their field. You may be aiming for 50-200 search results to review for your literature section, but with the overwhelming number of articles published every day, tracking connections between research papers manually becomes nearly impossible.

This is where literature maps become helpful. A literature map organizes, connects, and structures existing literature on a specific topic. These visual tools provide a clear overview of how different studies relate to each other, help you see patterns you might miss otherwise, and can reveal literature you may have overlooked. The scoping and mapping stages are often considered the two most important parts of the literature review process. Your task is not to read everything you encounter, but to make informed decisions about relevance and focus on what matters most for your work.

Many PhD students I have worked with express frustration with literature overload or simply want a more systematic approach to managing their research workflow. Literature mapping tools can help address these challenges. You can create these maps manually or use specialized software to speed up the process and uncover connections you might have missed. The question becomes: which tool should you choose?

Connected Papers and Litmaps are two prominent platforms available in 2025, each taking different approaches to visualizing research connections. Through this comparison, I aim to help you understand their respective strengths and limitations, so you can determine which one offers better value for your specific PhD research needs. While there is a price difference between these tools, the decision involves more than just cost considerations.

Understanding Literature Maps and Their Role in PhD Work

Literature maps function as visual tools that show connections between research publications. The key difference from traditional literature searches is that a literature map reveals how articles connect through citations, themes, or methodologies rather than simply providing a list of potentially relevant papers. This approach helps you understand the structure of knowledge in your field and identify relationships between studies that might not be immediately obvious.

What Literature Maps Actually Do

A literature map organizes existing literature on a particular topic by displaying connections between publications. You can create these maps manually or use specialized software that analyzes metadata such as citations, authors, and keywords. The goal is to transform what can feel like an overwhelming research landscape into something more manageable - a visual representation that highlights relationships you might otherwise miss.

I find that many students initially expect literature maps to solve all their research problems, but it's important to understand what they can and cannot do. They excel at showing patterns and connections, but they cannot determine which studies are most relevant to your specific research question. That decision-making remains your responsibility.

Three Main Applications for PhD Research

Literature maps serve several practical purposes in PhD work:

Organizing Literature Reviews: Maps provide structure for organizing information, helping you identify patterns and themes across different studies. This visual approach can improve the clarity of your literature review by showing how different research streams connect to each other.

Understanding Author Impact: You can create author-centered maps to see how a researcher's work has influenced a field over time. This becomes particularly useful when you want to understand the development of key ideas or identify influential researchers in your area.

Finding Research Gaps: Perhaps most valuable for PhD students, literature maps can reveal areas where research is lacking. When you see where publications connect (and where they don't), you can spot potential gaps worth exploring in your own work.

Two Approaches to Mapping Literature

Topic-based maps organize literature around specific themes or concepts, typically placing the main topic at the center with related sub-topics branching outward. This shows how different research streams relate to each other within a particular domain.

Author-based maps focus on a researcher's body of work, demonstrating their impact on the field over time. This approach helps you understand how individual researchers have contributed to knowledge development.

The tools we're comparing - Connected Papers and Litmaps - take fundamentally different approaches to creating these visualizations. Connected Papers creates graph-based networks that cluster similar works together, even when there are no direct citations between them. Litmaps generates citation-based graphs where papers are positioned along chronological and impact axes. This difference in visualization approach affects how effectively each tool helps you discover connections and identify research opportunities.

How These Tools Actually Work: What You Need to Know

Both Connected Papers and Litmaps can help you navigate academic literature, but their approaches differ significantly. Having tested both tools extensively during my research, I can share some insights about how they function in practice.

Search Capabilities: Starting Points and Algorithms

Connected Papers builds literature maps using a single seed paper, analyzing its co-citation network through Semantic Scholar data. This approach works well when you have identified one key paper in your field, but it does limit broader exploration since you can only work from one starting point at a time.

Litmaps takes a different approach by allowing you to use multiple papers as input for discovery. This creates more comprehensive starting points for your literature exploration. The tool offers three distinct search algorithms that I have found useful in different situations:

• Shared Citations & References (their default option)
• Common Authors (helpful for identifying key research teams)
• Similar Text (AI-driven semantic analysis)

Map Visualization: Different Ways of Seeing Connections

The visual approaches of these tools reveal different aspects of the literature landscape. Connected Papers creates a graph-based network that clusters similar works together, even when there are no direct citations between them. Each node's size represents citation count, while color indicates publication year (darker means more recent).

Litmaps generates citation-based graphs positioned along customizable axes. The default setup shows publication date on the X-axis (older papers on the left, newer on the right) and citation count on the Y-axis. This timeline approach allows you to quickly spot impactful recent papers in the top right corner of the visualization.

Customization Options: Flexibility for Your Workflow

When working with Connected Papers, you have basic filtering options by year, citations, or open-access availability. You can switch between graph and list views and sort results by various metrics. This simplicity can be beneficial when you want quick results without much setup.

Litmaps provides more extensive customization options. You can modify node size and axes to display different metrics including connectivity, reference count, and momentum. What I find particularly useful is the ability to manually arrange papers and create custom categorizations by subtopics. This feature becomes valuable when you need to organize literature for specific sections of your thesis.

Interface and Learning Curve

Connected Papers features a straightforward interface that works well for beginners seeking quick literature exploration. It generates results instantly and presents visualizations that are easy to understand.

Litmaps provides a more sophisticated approach, showing only the most relevant papers in manageable batches of 10. While it has a steeper learning curve, this more structured discovery experience can be particularly valuable for in-depth PhD research that requires systematic literature analysis. The additional complexity pays off when you need to conduct thorough reviews for your thesis chapters.

Getting These Tools to Work Within Your Research Process

The way these tools fit into your daily research routine matters more than their individual features. Your literature mapping process should make your PhD work easier, not add another layer of complexity to manage.

Setting Up Your First Literature Map

The process for creating maps differs considerably between these platforms. Connected Papers asks for just one seed paper to generate your visualization. You enter a paper's title, DOI, or URL, select from potential matches, and the tool generates a network graph. Node size represents citation count while color indicates publication year. This approach delivers immediate results but limits you to exploring connections from a single starting point.

Litmaps takes a different approach entirely. You can begin with one paper or select several works as origin points. You can also upload BibTeX, RIS, or PubMed files to initiate your map. After you collect relevant literature, Litmaps arranges papers on a customizable 2D graph with newer papers positioned on the right and highly-cited works toward the top. This flexibility in starting points can be particularly helpful when you already have several key papers in mind.

Managing Citations and References

Connected Papers supports basic citation management through BibTeX export. This allows you to manually import references into your reference manager, though it lacks direct integration with popular tools.

Litmaps and ResearchRabbit (another competitor) offer Zotero integration. ResearchRabbit provides bi-directional syncing where changes in Zotero automatically reflect in your literature maps and vice versa. This integration can save considerable time by eliminating duplicate data entry, though you should consider whether this added complexity fits your current workflow.

Keeping Track of New Publications

One significant difference lies in how these tools help you stay current with new research. Litmaps includes a "Monitor" feature that automatically sends weekly email alerts about newly published papers relevant to your collection. This proactive approach means you can stay updated without having to remember to check manually.

Connected Papers requires you to manually refresh your searches to discover new papers. This places the responsibility for staying current entirely on you, which can work well if you prefer controlling when and how you receive updates.

Working with Others

Both tools allow you to share your literature maps, but with different capabilities. Connected Papers offers basic sharing functionality. Litmaps and ResearchRabbit provide more extensive collaboration options including team sharing and annotations. ResearchRabbit allows you to add notes to papers, which can enhance collaborative research efforts if you work with others on related topics.

The choice between these approaches depends largely on your specific research style and needs. Litmaps offers more sophisticated workflow integration through multiple input options, automated monitoring, and stronger collaboration tools. These advantages may justify its higher cost for researchers who need comprehensive literature analysis capabilities.

Understanding Costs and Making Smart Decisions

The reality of PhD research is that budget constraints often influence which tools you can afford. Having worked with many students over the years, I understand that cost considerations can make or break your decision to invest in research tools. Each platform takes a different approach to pricing, and these differences have real implications for your research workflow.

Free Plans and Their Practical Limitations

Connected Papers offers what appears to be a generous free tier - all features included but limited to five graphs per month. When I first started using literature mapping tools, this seemed like plenty. However, I quickly discovered that serious PhD work requires more extensive mapping than I initially anticipated. You may find yourself running out of monthly allocations faster than expected, especially during intensive literature review phases.

Litmaps takes a more restrictive approach with their free plan, allowing only one map with up to 100 articles and basic search functionality. This limitation becomes apparent almost immediately if you're conducting thorough literature reviews. Both platforms remove these constraints through their premium subscriptions, but the question becomes whether the investment is worthwhile.

Academic Pricing and Student Reality

Litmaps deserves credit for recognizing academic budget constraints. They offer a substantial 75% discount for academics with institutional email addresses, bringing the Pro plan to approximately £7.94/month (roughly $10 USD). This makes it considerably more accessible for PhD students. Additionally, they provide parity pricing based on location, which addresses the reality that research budgets vary significantly across different countries.

Connected Papers also acknowledges the financial challenges researchers face through their scholarship program. You can request discounted or free Premium access on a case-by-case basis, though this requires additional steps and approval.

Long-term Investment Considerations

For PhD projects that span several years (as most do), sustainable access becomes essential. Connected Papers offers predictable pricing, which helps with budget planning. Litmaps provides additional value through its LibKey integration, enabling direct access to institutional subscription papers - a feature that can save considerable time during literature reviews.

My Assessment of Value for Money

Despite the higher cost, I have found Litmaps to deliver better value for serious PhD research. The unlimited inputs, advanced search capabilities, and automatic weekly updates justify the premium price for most researchers. However, I want to be honest about the limitations of both approaches.

Connected Papers works well for occasional literature exploration, but I have seen students hit the monthly limits during critical phases of their research. Litmaps requires a financial commitment that may not be feasible for all students, despite the academic discount.

My recommendation is to consider the total cost of your PhD journey. The modest subscription cost often proves worthwhile when weighed against the time saved and improved research quality. However, if budget constraints are severe, Connected Papers' free tier may provide sufficient functionality for initial exploration, with the option to upgrade when necessary.

Key Differences at a Glance

When evaluating these tools, I find it helpful to look at the specific features that will matter most for your daily research workflow. The differences between Connected Papers and Litmaps become clearer when you examine how each tool handles the core functions you will use regularly.

Below is a breakdown of the main features that distinguish these platforms:

The most significant differences lie in search flexibility and workflow integration. Connected Papers excels at simplicity—you can start mapping immediately with just one paper. Litmaps requires more initial setup but offers greater control over how you discover and organize literature. This trade-off between ease of use and functionality often determines which tool works better for different types of research projects.

Making the Right Choice for Your Research

Having spent considerable time testing both platforms and observing how different PhD students use these tools, I can share some honest observations about which approach works better in practice.

Connected Papers offers an accessible starting point that many researchers find appealing. The straightforward interface and generous free tier make it easy to begin exploring literature connections. The semantic clustering approach works well for quick visualization when you need to understand a research landscape from a single paper. I have seen this work particularly well for preliminary exploration or when you are just getting familiar with a new field.

However, I have also observed that serious PhD work often requires more than what Connected Papers provides. This is where Litmaps becomes valuable. The ability to start with multiple papers makes a significant difference when you are conducting thorough literature reviews. The timeline visualization helps you see research progression more clearly, and the automatic weekly alerts solve a problem that many PhD students face - staying current with new publications without having to remember to check manually.

The price difference between these tools may initially seem significant. But I have found that PhD students who invest in Litmaps often report that the enhanced workflow integration and time-saving features justify the cost. The substantial 75% academic discount helps make this more reasonable for most PhD budgets.

Your choice depends on how extensively you plan to use literature mapping in your research. If you need occasional mapping for specific projects, Connected Papers serves that purpose adequately. But if literature review is central to your work - as it is for most PhD projects - Litmaps provides the depth and flexibility you will likely need. I have seen too many students start with basic tools only to find they need to switch to more capable platforms later in their research journey.

My recommendation is to consider your long-term research needs rather than just immediate requirements. For comprehensive PhD research that demands thorough literature analysis, Litmaps delivers better value despite its premium pricing. The investment in better tools often pays for itself through improved research quality and efficiency - something I wish I had understood earlier in my own academic journey.