bidict

Efficient bidirectional map data structures for Python.

EstablishedOpen SourceLow lock-in

Pricing

Free tier

Flat rate

Adoption

Stable

License

Open Source

Data freshness

Verified · Jul 12, 2026

Overview

What is bidict?

Bidict provides efficient and Pythonic bidirectional mapping capabilities, allowing developers to maintain consistent mappings between two sets of values. This is particularly useful in scenarios where reverse lookups are required without the overhead of maintaining separate dictionaries.

Key differentiator

Bidict stands out as an efficient, Pythonic solution for implementing bidirectional mappings with minimal overhead and comprehensive support for various use cases.

Capability profile

Capability Radar

Ease of StartEcosystemValueMaturityFlexibilityScale Ready

Honest assessment

Strengths & Weaknesses

↑ Strengths

Bidirectional mapping with efficient reverse lookups.medium

Support for various bidirectional map types (e.g., OrderedBidict).medium

Comprehensive test suite and documentation.medium

↓ Weaknesses

Limited language supporthigh

Bidict is primarily designed for Python, and there are no official versions or integrations for other programming languages.

Complex setup for non-trivial use casesmedium

Setting up bidirectional mappings with complex data structures can require a deep understanding of the library's internal mechanisms and Pythonic patterns.

Performance overhead in large-scale applicationshigh

Maintaining two-way consistency between mappings can introduce performance bottlenecks when dealing with very large datasets or high-frequency updates.

Documentation lacks advanced usage examplesmedium

While the basic documentation is comprehensive, it falls short in providing detailed examples for more complex use cases and edge scenarios.

Fit analysis

Who is it for?

✓ Best for

Developers working on projects requiring efficient bidirectional data structures.

Applications where reverse lookups need to be performed frequently and efficiently.

✕ Not a fit for

Projects that do not require bidirectional mapping capabilities.

Scenarios where the overhead of maintaining a bidirectional map is unnecessary or inefficient.

Cost structure

Pricing

Free Tier

Available

Open source — free to use

Starts at

$0

Model

Flat rate

Enterprise

None

Performance benchmarks

How Fast Is It?

Ecosystem

Relationships

Next step

Get Started with bidict

Step-by-step setup guide with code examples and common gotchas.

View Setup Guide →