Updated 2026-08-01 · held-out answer containment · live compiler workloads

Keep the answer. Drop the noise.

Most compressors cut tokens. SuperCompress is judged on a harder question: after compression, can the model still answer correctly? On primary held-out suites (real / fresh4 / fresh5), gold answers survive at 99.4% pooled (180/181) while mean token cut stays ≥55%. Fresh6 cold mix also clears the answer gate below.

Held-out answers 99.4% Pooled gold containment on real + fresh4 + fresh5 (seeds 4242 / 9091 / 6161).
Mean cut ~58–66% Token-weighted cut ~62–69% on the same held-out mixes — no restore-to-98% floor.
Oracle suite 100% Fixed 35% budget oracle recall on the public 8-seed suite (vs ~25% truncation).
Runtime ~47ms CPU policy path. Hosted neural ranking optional. No extra LLM call.

Why these numbers matter

For founders & PMs Lower bills, same answers

You pay for input tokens. Compression only helps if the model still gets the facts it needs. SuperCompress is built to cut waste without cutting the answer.

For engineers Oracle recall, not vibes

We measure whether answer-bearing lines survive. Fixed-budget head-to-head: SuperCompress 100%, H2O 97.9%, summarization 60.5%, truncation/FIFO 24.8%.

For agents & copilots Noise dumps are the point

Logs, RAG chunks, chat history, tool output — compiler mode removes everything it can while locking query-critical evidence. Savings scale with how noisy the dump is.

For ops Deploy without drama

neural ranking, ~47ms on CPU, no GPU queue, no second model call. Drop it in front of OpenAI, Claude, Gemini, or local models.

Same budget. Who keeps the answer?

Fair test: every method keeps only 35% of tokens. The only question is whether the answer-critical lines are in that 35%.

Method Answer-critical kept What that means Latency Footprint
FIFO / Truncation 24.8% Drops the middle — often where the answer lives ~42–46 ms Rule-based
Summarization 60.5% Rewrites context; can invent or omit details ~48 ms + LLM Extra model call
H2O 97.9% Strong attention baseline from serving research ~42 ms Attention-heavy
SuperCompress Best 100% Every answer-critical line kept ~47 ms neural ranking, CPU

8 project seeds, fixed 35% token budget, refreshed from the public suite (July 2026). “Answer-critical kept” = oracle recall. Entity recall on this suite: 72.9% for SuperCompress / H2O / truncation (same kept-entity set under fixed budget).

How SuperCompress compares to common alternatives

Baseline Query-aware? Public result / claim Why teams still pick SuperCompress
Headroom Mostly type / tool-output aware Publicly claims ~15–20% fewer tokens for coding agents We score directly against the question and report answer-critical retention
Rule heuristics / Caveman-style No Prompt-dependent shortcuts Query-aware ranking instead of fixed windows
Truncation No 24.8% critical kept on this suite Preserves critical lines anywhere in the context, not just head/tail
H2O Yes (attention) 97.9% on this suite Higher critical retention here, with a tiny CPU policy instead of attention eviction
SuperCompress Yes 100% critical kept Best quality metric + smallest practical footprint

Headroom’s public claim is product marketing on different workloads — included for landscape context, not as an apples-to-apples lab score.

Compiler mode — remove everything you can, keep everything important

No fake “keep 35%” floor. Compiler mode drops non-essential context until only what’s needed for the question remains — then verifies that answer-critical content is still there. Noisy dumps compress hard. Dense coding context compresses less. That’s intentional.

Workload Original After Removed Savings Critical kept
Literature study context 1,454 1,052 402 27.6% 100%
Dense coding session 1,020 397 623 61.1% 100%
Docs / markdown 1,195 59 1,136 95.1% 100%
Agent incident log 1,074 232 842 78.4% 100%
Token-weighted average 1,186 435 751 63.3% 100%

Measured 2026-08-01 with the live compiler engine on bundled long-context presets. Critical kept = independent answer-critical line retention vs the original text.

Held-out answer containment (anti-overfit)

Separate from the fixed-budget oracle suite: compress real LongBench dumps + brand-new OOD wiki/RFC/README haystacks, then check whether the gold answer string is still present. Gates: ≥98% answer retention, ≥55% mean cut, ≥55% token-weighted cut. No circular restore floor.

Suite Seed Answer kept Mean cut Token-weighted cut Gates
Real (ood_fresh3 + hotpot/2wiki/multifield/qasper) 4242 98.4% (61/62) ~57.8% ~64.7% pass
Fresh4 (ood_fresh4 + musique/trivia/narrative/samsum) 9091 100% (57/57) ~66.1% ~68.8% pass
Fresh5 (ood_fresh5 + hotpot/2wiki/multifield/qasper) 6161 100% (62/62) ~57.8% ~61.6% pass
Fresh6 cold (ood_fresh6 hard + musique/trivia/narrative/2wiki) 3377 98.6% (70/71) ~68.2% ~72.5% pass

Artifacts: web/assets/data/real-benchmark-latest.json, fresh4-benchmark-latest.json, fresh5-benchmark-latest.json, fresh6-benchmark-latest.json. Refreshed 2026-08-01 night. Primary bundle pooled answer 99.4% (180/181), pooled TW cut 65.4%. Fresh6 still has one multi-hop drop (Parkinson) inside the 98% gate.

At a glance

Critical context retained at 35% budget: SuperCompress 100%, H2O 97.9%, summarization 60.5%, FIFO and truncation 24.8%
Fixed budget: who still has the answer?
Compiler mode token savings by workload with 100% critical content kept
Compiler mode: savings follow how noisy the dump is

Impact when this runs at scale

SuperCompress removes prompt text before inference, so fewer tokens reach the GPU and the provider performs less prefill work. Estimates use documented assumptions (2,500 tok/GPU-s, 150W GPU, an estimated 55% inference-memory share for provider-managed KV state, 0.417 kg CO₂/kWh) and ~800 tokens saved per call.

Scale Tokens avoided kWh saved CO₂ avoided
1,000 calls ~800K ~0.03 ~0.01 kg
1M calls ~800M ~29 ~12 kg
10M calls ~8B ~290 ~120 kg

Methodology: Environment guide. Real savings depend on model and workload.

Questions people actually ask

What is “answer-critical” / oracle recall?

It’s the share of lines that contain the information needed to answer the question that still appear after compression. 100% means nothing required for a correct answer was deleted. That’s the metric that protects quality.

Why do all methods show ~65% tokens saved in the first table?

Because that test forces the same budget: keep 35% of prompt tokens, drop 65%, so tokens_saved_pct is ~65% for every method. It’s a quality contest, not a savings contest. The interesting number is who still has the answer afterward.

Why do savings vary by workload?

Noisy dumps (logs, markdown chrome, agent traces) compress hard — often 70–95%. Dense literature or tightly relevant coding context keeps more by design. The preset suite averages ~63% token-weighted savings with 100% critical retention.

Is this better than just truncating my prompt?

At the same size budget, truncation kept ~25% of critical lines on our suite. SuperCompress kept 100%. Truncation is fine when the answer is always at the edges. Real agent and RAG dumps put the answer anywhere.

Do I need a GPU?

No. SuperCompress runs on CPU with a learned query-aware neural policy and ~47ms average latency on the suite. Zero GPU time, zero extra LLM calls.

Can I try it on my own traffic?

Yes — use the playground, the hosted API, or the coding-agent MCP plugin. You’ll see tokens removed and critical-retention metadata on each call.

Try SuperCompress on your own context

Paste your long prompts and see exactly how much can be removed while keeping what matters.

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