libmdbx vs LMDB
libmdbx: Heavily reworked LMDB descendant: memory-mapped ACID B+tree with auto-growing files. LMDB: Tiny memory-mapped B+tree with ACID transactions and lock-free readers; reached 1.0 in 2026.
key differences
- These two are very similar on paper. Compare ecosystems, pricing and team familiarity.
choose libmdbx for
- +Blockchain node state and indexes
- +Read-heavy embedded storage needing LMDB semantics
- +Replacing LMDB where auto-resizing is needed
best at · Embedded, Metadata
choose lmdb for
- +Read-heavy embedded indexes and caches
- +Directory services (OpenLDAP back-mdb)
- +Blockchain and wallet state
- +ML dataset storage with fast random reads
best at · Embedded, Metadata, Local-first
libmdbx vs LMDB: FAQ
What is the difference between libmdbx and LMDB?
libmdbx: Heavily reworked LMDB descendant: memory-mapped ACID B+tree with auto-growing files. LMDB: Tiny memory-mapped B+tree with ACID transactions and lock-free readers; reached 1.0 in 2026.
When should I choose libmdbx over LMDB?
Choose libmdbx for blockchain node state and indexes; read-heavy embedded storage needing LMDB semantics; and replacing LMDB where auto-resizing is needed. Choose LMDB for read-heavy embedded indexes and caches; directory services (OpenLDAP back-mdb); and blockchain and wallet state.
Is libmdbx or LMDB more popular?
LMDB ranks #47 on the WhichDB Score (39.7/100) and libmdbx ranks #394 (4.9/100). Popularity is not fit: check the requirements that matter for your project.
Are libmdbx and LMDB open source?
Yes. libmdbx is open source. License: Apache License 2.0. Yes. LMDB is open source. License: OpenLDAP Public License 2.8.