Benchmarks

78.4% on LongMemEval.
64–65% on LoCoMo.
Every prediction published.

memnos is measured on the public long-term-memory benchmarks with a named judge and an open harness — and we ship the per-question predictions, so you can check every answer yourself. Reproduce any number in one command.

LongMemEval

500 questions
78.4%

The 500-question run on Supermemory's open MemoryBench harness — gpt-4o as both answerer and judge. Retrieval isn't the bottleneck (MRR 0.79 / NDCG 0.80); memnos surfaces the right memory, and the answer model does the rest. Strongest on factual recall (assistant-facts 98%, user-facts 93%); weakest on preference (47%) — the full per-type breakdown and every prediction are in the repo.

LoCoMo

full 10 · 1,542 questions
64–65%

The full conversation set, scored by a gpt-4o judge across three independent from-scratch ingests (65 / 64 / 65) — a band, not a single lucky run. Every prediction for every run is committed to the repo under benchmarks/results/.

# reproduce it yourself — full conversation set, from scratch
$ python benchmarks/locomo_eval.py --sample-ids 0,1,2,3,4,5,6,7,8,9
gpt-4o judge : 64–65%   # three independent ingests: 65 / 64 / 65

# LongMemEval, 500 questions, via Supermemory's MemoryBench harness
gpt-4o judge : 78.4%   # predictions published
# every run's per-question predictions live in benchmarks/results/
No self-graded headlines

Numbers you can check, not just trust

Plenty of memory products publish one big number with no judge, no rubric, and no way to re-run it. Here's the standard memnos holds itself to instead.

Named judge & rubric

Every number says exactly who graded it and how — gpt-4o, with the rubric in the open. No model quietly grading its own homework.

Predictions in the repo

Open any run under benchmarks/results/ and read what memnos actually answered for each question — and how the judge scored it.

Open harness

The eval script ships in the repo. Swap the judge, change the rubric, re-run from scratch — and you get the same numbers we did.

The whole judge band

We publish the same answers under strict, standard, and lenient grading — so no rubric can flatter the number without you seeing the full spread.

One set of answers · three rubrics · all published

We show the whole band. Most show you one point on it.

~44%
Strict
exact, no benefit of the doubt
~57–65%
Standard
reasonable correctness
~85–88%
Lenient
"one right item ⇒ correct"

The same memnos answers, on the same benchmark, score anywhere from ~44% to ~88% purely on how strictly you grade. A vendor showing a single big number is choosing the friendly end of that band and not telling you. We publish all of it and stand on the standard-judge result — so the number you reproduce is the number we lead with.

These numbers come from an engine that does no LLM call at query time — recall is vector + full-text + a local reranker, fully deterministic. So the score you reproduce from the repo is the behavior you get in production: same retrieval, same ranking, every run.

Three questions for any memory benchmark — including ours

memnos answers yes to all three. Use them on every vendor you evaluate.

Who graded it — and is the rubric published? memnos: gpt-4o judge, rubric in the open, the full strict-to-lenient band shown.

Can I see the per-question predictions? memnos: yes — every run's predictions are committed to benchmarks/results/.

Can I re-run it myself? memnos: yes — the harness ships in the repo; clone it, run it from scratch, get the same band.

Memory you can verify,
not just trust

Strong numbers, an open harness, and per-question predictions you can read. Self-host it and check every claim on this site for yourself.