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Reflection · Official-source model record

Beam 1.0 501B A23B

Beam · Version Beam-1.0-501B-A23B

AvailableChecked Oct 23, 2026
Editorial (1) ↓Download model brief (.md)

Publisher-sourced inventory. Specifications come from official documentation and model cards. “Not documented” means we have no verified value. This inventory is separate from our editorial reviews.

Coverage & sources ↗

Current catalog answers

What to know about Beam 1.0 501B A23B

AI-compiled from linked model documentation. This is a catalog reference, not an independent performance review. Catalog checked October 23, 2026.

Which Beam 1.0 501B A23B does this page describe?

Beam 1.0 501B A23B is a model record from Reflection in the Beam family. Source

The recorded model identifier or checkpoint is Beam-1.0-501B-A23B. Use that exact identifier when checking documentation or a provider listing. Source

How can you access Beam 1.0 501B A23B?

The catalog documents API and Open weights access for Beam 1.0 501B A23B. Source

As of the catalog check, this version was listed as available. Source

For API use, confirm the exact model identifier, your account and region, and the endpoint's current limits in the linked documentation. An API listing does not establish access through a consumer subscription.

Open weights means the model weights are distributed for use under their stated terms. It does not establish a hosted API, an open-source license, or a hardware requirement. This record documents API access separately.

What are Beam 1.0 501B A23B's context and output limits?

The documented context window is 1,048,576 tokens. Source

The documented maximum output is 131,072 tokens. Source

Context, input and output limits describe different constraints. Do not add the figures together to infer a larger window. Check the endpoint's accounting for conversation history, system instructions, tools, media and generated tokens; a documented maximum is not a guarantee of answer quality or a measured usable capacity.

What dates are documented for Beam 1.0 501B A23B?

Knowledge cutoff: June 30, 2026. Source This labels the documented knowledge boundary; it is not a promise that every earlier fact is known or correct.

Release date: October 16, 2026. Source This is a release milestone, not a knowledge or training cutoff. The source labels this “Public open-weight release.”

Retrieval or web tools can supply newer information at run time. That does not change the model's recorded training or knowledge dates, and this record does not establish that a particular endpoint includes those tools.

What can Beam 1.0 501B A23B receive and generate?

Documented inputs: text. Source

Documented outputs: text. Source

Input support and output generation are separate capabilities. Reading an image does not establish image generation; a text output listing does not establish speech output. File sizes, formats and media limits depend on the documented implementation.

What license is recorded for Beam 1.0 501B A23B?

The recorded license label is Apache-2.0. Source

Read the linked license and associated use terms for this exact version before redistribution, commercial deployment or fine-tuning. A label alone does not establish every permission, restriction or obligation, and it does not determine the terms of a separate hosted service.

The documented record

Specifications, with their sources.

A missing value remains unknown. Input limits, output limits and the total context window are separate measurements.

Publisher
ReflectionSource ↗
Family
BeamSource ↗
Version
Beam-1.0-501B-A23BSource ↗
Availability
AvailableSource ↗
Access
API · Open weightsSource ↗
Inputs
TextSource ↗
Outputs
TextSource ↗
Context window
1,048,576 tokensSource ↗
Maximum input
Not documented
Maximum output
131,072 tokensSource ↗
Knowledge cutoff
Jun 30, 2026Knowledge cutoff · day precisionSource ↗
Training-data cutoff
Not documented
Training completed
Not documented
Release date
Oct 16, 2026Public open-weight release · day precisionSource ↗
License
Apache-2.0Source ↗
Input price / 1M tokens
Not documented
Output price / 1M tokens
Not documented

Read this with the numbers.

Public API documentation example supplies exact context/output integers; organization defaults and limits can differ. Open-weight release is separate from API created date.

Model identifiers and aliases 0

No additional identifier has been verified.

Follow the evidence

Official sources.

  1. Beam 1.0 501B A23B official reference ↗developers.reflection.ai
  2. beam-is-available ↗reflection.ai

From the Headless Thrones newsroom

Editorial about Beam 1.0 501B A23B

1 published article linked to this exact model. Newest first.

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By Headless Thrones · AI models reporter · AI author

Your starting point

Beam 1.0 501B A23B

Reflection · API / Open weights

Browse all models ↗
Inputs
TextSource ↗
Outputs
TextSource ↗
Context window
1,048,576 tokensSource ↗
Knowledge cutoff
Jun 30, 2026Knowledge cutoff · day precisionSource ↗

A place to begin comparing

1,200 models to consider.

Matches must share an access route, support every documented input type of your starting model, and return text. When both publish a context limit in the same field, the candidate must fall between half and twice that limit. Unknown or differently defined limits remain as broader matches, after verified near-context matches. Within each group, recent documented releases appear first. These criteria do not establish equal quality. The full current inventory is considered.

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Text input; text output · Shared access: API · Documented context within ½–2×

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Text input; text output · Shared access: API · Documented context within ½–2×

Xiaomi

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Text input; text output · Shared access: API · Documented context within ½–2×

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NVIDIA

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A record you can follow

The source belongs beside the fact.

Official sources

Model records cite the developer’s documentation, release notes and model cards. A listing alone is not a tested service or a recommendation.

Dates mean different things

Knowledge cutoff, training-data cutoff, training completion and release date are separate fields. A model’s name or repository upload date does not establish any of them.

Limits need context

Some publishers use rounded K/M token figures. Deployment, reasoning settings and regional access can change usable limits. Read the source before choosing.

Coverage and last check

Independent editorial model library assembled from primary vendor documentation and official publisher model cards. This is a dated, auditable inventory of the sources reviewed, not a claim to every model worldwide. First-party language-model inventory for OpenAI, Anthropic, Google Gemini/Gemma, xAI, Meta and Reflection. Includes vendor-listed legacy/retired identities with explicit statuses; official pretrained and instruction-tuned checkpoints remain distinct. Excludes embeddings, moderation/guard models, image/audio/video-only generation, community fine-tunes, speculative draft helpers, format/runtime/quantization duplicates, and PaliGemma dataset-specific benchmark fine-tunes. Availability means documented vendor API or downloadable official weights, not guaranteed account eligibility. Unknown specifications and dates remain null. Rounded K/M limits preserve vendor granularity; exact integers are used only where documented. No OpenRouter facts are used. Primary-source inventory of language-capable models from Alibaba/Qwen, DeepSeek, Moonshot, MiniMax, Z.ai, ByteDance Seed, Tencent, Baidu, Xiaomi, StepFun, 01.AI, Shanghai AI Laboratory, Baichuan and OpenBMB. Includes full reachable official public weight inventories plus documented hosted API models and explicit retirements. Embeddings, reward/classifier/router/tokenizer/draft-head components, standalone OCR/document converters and image/video/audio-only generators are excluded; multimodal language models retained. Official packaging variants are folded into aliases where a canonical listing was identifiable; remaining research/base/SFT variants retain exact identities. Not a guarantee every historical/private/regional model is available. Unknown specifications remain null; K/M API display quantities use decimal normalization where explicitly noted, rather than implying verified exact serving ceilings. Model-name dates and repository creation timestamps are never used as release/training dates. Open weights does not mean unrestricted or OSI-open-source licensing. Some model-card bodies were unreachable; their public inventory metadata is retained and disclosed. Official Mistral, Cohere, AI21, NVIDIA Nemotron, Microsoft Phi/MAI, Amazon Nova, IBM Granite, AllenAI OLMo/Molmo, TII Falcon, Nous Research, Arcee and Essential AI model inventory checked 2026-10-23. Includes base, instruction, reasoning, coding and text-producing multimodal models, including legacy API versions. Excludes embeddings/rerankers/reward and safety classifiers, image/audio/video-only generation, robotics-only models, duplicate quantization/runtime packages, adapters, intermediate checkpoint experiments, and third-party mirrors. Arcee coverage focuses on its named product families rather than exploratory merge repositories. Repository listing means listed, not independently verified API availability. K/M figures are nominal decimal normalizations when the source supplies shorthand; deployment-specific exact token limits may differ. Unverified values remain null. This is a source-backed inventory, not a complete claim-level independent editorial review. Supplemental official Liquid AI, Reka and Inception generative language catalog. Excludes media-only generators and decision/classification-only models. No assumed training dates.

Catalog edition updated . Source links are provided on each model record.

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