Models / AI21/ Jamba Large 1.7

Jamba Large 1.7

AI21 · released Jul 2, 2025 · ai21labs/AI21-Jamba-Large-1.7

Input: text. Output: text.InputOutput
Type
Open weightsCustom licence
Params
399B
Context
256K

about 192K words of context · download allowed, licence restricts use

Our take

Written Aug 3, 2026

Jamba Large 1.7 is a 398.6-billion-parameter text model from AI21 with a 256,000-token request limit and a custom restricted licence. It has broad benchmark coverage with stable measurements, though only two hosts carry it and at identical rates.

Who should pick it

Pick this for long-context text tasks that need a quarter-million tokens in one request, or for coding workloads where its measured coding score is the strongest of its six tracked categories. Use it when you are comfortable with AI21's own hosting at 34 tokens per second. Skip it if you need price competition between providers, a permissive licence, or strong mathematics performance — its maths score trails its coding score by a wide margin.

The case for it

  • Broad benchmark coverage with stable, reproducible measurement: six Arena benchmarks measured twice within two days, all within 0.1% score drift.
  • Largest measured context window in this data set, at 256,000 tokens.
  • Coding benchmark is the strongest of its six measured categories, ahead of its next-best by a 67.3-point margin.

The case against it

  • Mathematics is the weakest of its six measured categories, trailing its coding score by a 67.3-point gap.
  • No price competition between its two hosts, which charge identical rates.
  • Restricted licence limits commercial flexibility — not Apache, MIT, or standard commercial terms.
00

How good is it?

IntelligencePuzzles, maths, exam questions

1 of 5

Arena Text (overall)128th of 143 · 1289.2

Arena Hard Prompts 131st of 143Arena Maths 129th of 139

CodingWriting and fixing code on its own

1 of 5

Arena Coding129th of 143 · 1312.2

Arena Coding is the only board that has scored it for this.

AgenticPlanning, calling tools, staying on task

not measured

Nobody we watch has scored Jamba Large 1.7 for this. We would take the rating from Arena Agent (IPS).

WritingWe do not rate this

Scored, not ratedThe placings are on the right.

Two boards come close and neither tests writing: Arena Creative Writing asks people which of two replies they prefer, and LiveBench Language tests whether a model understood a passage. So we show where Jamba Large 1.7 placed and give it no mark out of five.

Arena Creative Writing 124th of 143 · 1261.2
Also scored, on boards we give no mark for
Arena Instruction Following 130th of 143

These tests check whether a model follows instructions — a precondition for all the work above, but not a measure of how well that work is done, which is why they get no rating.

Every published score for this model6 scoresEvery figure we hold, from 6 boards, with who ran it and a link to the source — including the boards no rating above is built on.
1312.2independentsource ↗
1283.6independentsource ↗
1244.9independentsource ↗
1289.2independentsource ↗
01

Can you run it yourself?

Fits in memory
weights load entirely on the card
Spills to system RAM
some weights offload; much slower
Too large
will not load even with offload
est
size is calculated; the verdict could change by 10%
A card many people ownToo large

GeForce RTX 4090 · 24 GB

Weights at Q4_K_M251.3 / 24 GBest
Usable contextNot calculated for spilled setups
Decode speedNot estimated for spilled setups

Too large for this card. The weights do not fit even with part of them offloaded to system memory.

One step upToo large

Apple M1 Pro (16-core GPU) · 32 GB

Weights at Q4_K_M251.3 / 32 GBest
Usable contextNot calculated for spilled setups
Decode speedNot estimated for spilled setups

Too large for this card. The weights do not fit even with part of them offloaded to system memory.

Comfortable fit

On a MacFits in memory

Apple M3 Ultra (80-core GPU) · 512 GB

Weights at Q4_K_M251.3 / 512 GBest
Spare memory123.2 GB spare
Usable context131K of 256K
Decode speed2 tok/sest

Room to spare. 123.2 GB spare means a 10% error in the size would not change the answer.

Your hardware
Checking your profile…

Memory use by level

Against a 24 GB card.

Q4_K_M
recommended
251.3 GBest
Too large
Q5_K_M
294.8 GBest
Too large
Q8_0
440.5 GBest
Too large

All 3 sizes here are calculated, not measured. We hold no measured file for this model, so each size comes from the parameter count and every verdict above inherits that uncertainty.

Check against your own machine → · All 71 devices, with every size →

02

Or rent it from someone else

Cheapest published offer

Cheapest of 2 live listings. Picked at the widest standard context we hold, within one quantisation slice, so the numbers beside it are a price one host actually charges.

per 1M tokens
$2.00 in / $8.00 out
Context served
256K
Throughput
Not measured
Current provider offers with price, context and prompt-privacy answers
ProviderIn / out per 1M tokensContextThroughputTrains on promptsLogs promptsZero retention
OpenRouter$2.00 / $8.00256Knot measuredUnknownUnknownUnknown
AI21fp8$2.00 / $8.00256K53 tok/sNoYesunknown periodUnknown

Across the 2 listings we hold: 1 say they do not train on prompts, 0 say they do and 1 do not say. 0 appear in the zero-retention registry we check; the rest are unknown to us rather than confirmed either way.

What each host's API supports

From the parameter list each endpoint publishes. Streaming is omitted: nothing we hold reports it, for any model.

Supported
Not supported
Not published
host gave no parameter list
API features per host
ProviderTool callingJSON outputStrict schema
OpenRouter
AI21fp8

Tool calling: 2 of 2 listings say yes. JSON output: 2 of 2 listings say yes. Strict schema: 0 of 2 listings say yes, 2 say no.

03

When we formed this view

Dates behind this page

Aug 2, 2026BenchmarkScored 1312.2 on Arena Codingleaderboard
Aug 2, 2026BenchmarkScored 1261.2 on Arena Creative Writingleaderboard
Aug 2, 2026BenchmarkScored 1283.6 on Arena Hard Promptsleaderboard
Aug 2, 2026BenchmarkScored 1266.5 on Arena Instruction Followingleaderboard
Aug 2, 2026BenchmarkScored 1244.9 on Arena Mathsleaderboard
Aug 2, 2026BenchmarkScored 1289.2 on Arena Text (overall)leaderboard
Jul 27, 2026Benchmark updatejamba-1.5-large enters LMArena at 1289 Elo8662 votes
Jul 26, 2026ListedListed on LLMapfirst indexed by our pipeline
Jul 2, 2025AnnouncedJamba Large 1.7 announced by AI21

Prices last checked 6h ago

What we do not know about this model yet

  • We hold no measured file for it, so all 3 sizes on this page are calculated from the parameter count.
  • Nothing we hold says whether an endpoint streams, so we do not show it either way.
  • 1 of 2 listings do not say whether they train on prompts.
  • We hold no cached-input rate for any of its listings.
04

Licence and identifiers

What the licence allowsCustom licence, what it allows commercially, and the identifiers you need to pull this model — its Hugging Face repo, our slug and a machine-readable card.

Licence

Custom licence

restricted_openCustom licence — review the terms

This model ships custom license terms that don't map to a known template. We haven't parsed them, so commercial use, redistribution and derivatives are unverified — review the original terms before shipping.

Identifiers

Modality record
text->text
Catalogue slug
ai21-jamba-large-1-7

Machine-readable model card (omc.json) →

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