Bible Brain API Review (2026): Free Audio Bible Catalogue

Starting price: Free
Free tier: Yes
Platforms: REST API - Web - iOS - Android
Developer: Faith Comes By Hearing
Launched: -
Updated: Aug 5, 2026

1,477 (vendor page)Languages with text

1,381 (content inventory)Languages with audio

231 (January 2022)Bibles with verse timings

1,500 requests / 5 minRate limit in server code

Free, no licence feesCost

The verdict

Bible Brain is the only practical way for an outside developer to reach a dramatized, multi-voice audio Bible catalogue on this scale, and it costs nothing. Build on it if you are shipping a free ministry app and can live with an approval-gated key, a licence that forbids charging your users, and documentation that has visibly drifted since 2022. Look elsewhere if the product needs to earn money, or if you only need English text.

Try Bible Brain API ↗

Opens faithcomesbyhearing.com

Bible Brain is the developer-facing side of Faith Comes By Hearing, the Albuquerque nonprofit that has spent since 1972 recording Scripture for people who do not read it. That history is the whole point. Most Bible APIs are text pipes with an audio afterthought bolted on; Bible Brain is an audio catalogue that also happens to serve text, and the difference shows up in the identifiers, the endpoints and the licence.

The number quoted around this API is usually wrong. Directory listings describe it as serving "Bible text, audio, and video in 2,695 languages"; the Faith Comes By Hearing homepage advertises "Audio Bibles in 2,749 languages and counting". What the vendor prints on the Bible Brain page itself is narrower and different in kind: text in 1,477 languages, with no count given for audio or video at all. The larger figures describe a recording programme spanning decades, not the subset an API key reaches.

The closest thing to a real inventory is the CSV the Available Content page offers for download. It lists 2,004 Bibles across 1,666 ISO 639-3 language codes: 1,381 with audio, 1,263 with text, 1,058 with at least one Gospel Film. It also carries a last-modified date of 4 May 2022, so treat it as a floor. The shape is the interesting part. On that snapshot, 369 languages had audio and no text at all, against 251 with text and no audio - which is what you would expect from an organisation whose stated premise is that "70% of people alive today primarily learn through audible communication".

Access is free in the strict sense that the licence says so - Section 6 states that "No license fees or other payments will be due under this Agreement" - and unfree in a way that will end some projects before they start. The same licence conditions your key on enabling "your End Users to access DBP Content completely free of charge", and on operating in accordance with the Faith Comes By Hearing Statement of Faith. This is a ministry API, drafted as one.

✓ The good

Dramatized audio at catalogue scale - the fileset naming convention has a dedicated drama flag, where 2 means multi-voice with background music and 1 means non-drama, so you can filter for the theatrical recordings rather than guessing
Verse-level audio timings - as of January 2022 the docs claim exact verse start times for 231 distinct bibleIds, and a /timestamps endpoint that lists which filesets currently have them, which is what makes karaoke-style text-and-audio sync and search-to-audio-position possible
Genuinely free with no fees clause - Section 6 of the API License Agreement rules out licence fees or other payments, and there is no metered tier, no seat count and no paid upgrade anywhere on the developer site
Bandwidth-aware audio formats - alongside 64kbps mp3 there is 16kbps Opus in webm, which the docs claim is "comparable to 64kbps mp3" for spoken word, plus HLS streams for adaptive delivery
Limited offline download is actually permitted - the /download/list endpoint enumerates the filesets your key may cache inside your app, which almost no other Bible content licence allows at all
The API server is open source - the PHP implementation behind Bible Brain is published as faithcomesbyhearing/dbp under the MIT licence, so undocumented behaviour can be read rather than guessed at

✗ Watch out

No commercial product may be built on it - the licence permits your key only if "You enable your End Users to access DBP Content completely free of charge", which rules out subscriptions, one-time purchase apps and paid tiers that touch this content
The key is approval-gated at sole discretion - you must supply your name, email and a description of intended use, and the licence states "We may approve or deny your API Key request at our sole discretion" and that the key "may be revoked or limited by us at any time"
Your app must conform to a Statement of Faith - the guidelines require use "in accordance with FCBH's Statement of Faith" and Mission Statement, and make you police End Users who breach them
No rate limit is published - the only figure available is a throttle of 1,500 requests per 5 minutes in the open-source server config, and rejected requests carry no rate-limit headers
Documentation has visibly drifted - the licence and terms are both dated 4/15/21, the newest content note is January 2022, the Available Content CSV was last modified in May 2022, and the licence defines its own key terms by pointing at digitalbibleplatform.com URLs that no longer serve those pages
Content availability is filtered by the requesting IP - the server resolves an access type from the caller country and continent before deciding which filesets exist for your key, and the licence reserves the right to "freely remove, restrict, or limit access to all or any part of DBP Content at any time"

Best for

Free ministry apps serving oral and low-literacy communities
Bible tools needing dramatized audio in minority languages
Developers building verse-synced audio and text readers
Mission agencies distributing Scripture in low-bandwidth regions

Avoid if

Any paid, subscription or ad-funded Scripture product
English-only text projects with no audio requirement
Teams that need a published SLA and rate limit
Products requiring bulk export or a local content mirror

What Bible Brain API is

Bible Brain, also called Digital Bible Platform version 4, is a RESTful JSON API served from 4.dbt.io. Every request is a GET and every request needs a developer key passed as a query parameter. Content is organised in two layers: a bibleId, usually six characters in the form language code plus version code, groups all the formats of one translation, and a filesetId identifies a specific deliverable within it - a testament or partial selection, drama or non-drama, text, audio or video, at a specific encoding.

Text comes back inside the JSON response, in either plain or HTML and CSS formatted variants. Audio and video do not; the API returns signed CloudFront URLs pointing at the media. There are 31 documented paths, including timestamps, search, copyright, languages, countries, alphabets, numeral systems and a Jesus Film language route. The primary documentation is a Postman collection rather than a browsable reference site.

The audio is the product, and the identifiers prove it

On most Bible APIs, audio is a second-class field hanging off a translation record. On Bible Brain the drama type is a mandatory position in the identifier itself: in a filesetId like ENGESVN2DA, the 2 means multi-voice with background music and the 1 in its sibling means non-drama. Media type is another position - DA for 64kbps mp3, DV for mp4 delivered as multi-bitrate HLS, SA for a stream of the corresponding audio, with an opus16 suffix for 16kbps Opus in webm. A six-character filesetId with nothing after it is the plain text.

That design has a consequence worth naming. Because audio is primary, the catalogue includes languages with recordings and no published text - 369 of them in the May 2022 inventory. A text-first API cannot serve those communities at all, because there is nothing to serve. Faith Comes By Hearing also runs Oral Bible Translation projects that are voice-first, recorded without a written intermediate stage, and the documentation says that output flows into the same API. If your users cannot read, this is the difference between a product and an empty screen.

Verse timings and karaoke-style sync

The feature that separates a usable audio API from a list of mp3 links is alignment data, and Bible Brain has it. Two endpoints expose it: /timestamps returns the filesets carrying timing metadata, and /timestamps/{fileset_id}/{book}/{chapter} returns the start times themselves. The documentation is careful with its wording, describing them as "the approximate starting time for each verse", so build highlighting logic with some tolerance.

Coverage is partial and the published figure is old. The docs state that "As of January 2022, biblebrain provides the exact start time of each verse in 231 distinct bibleIds, and we are actively working to increase that count", with no updated number since. Call /timestamps and count what your own key can see rather than trusting the note. The documented uses are the two that matter: synchronising highlighted text against playing audio, and jumping playback to a keyword search hit.

Offline caching, which is allowed but fenced

For the low-connectivity contexts this platform exists to serve, the offline question is decisive, and the answer is a qualified yes. Section 4 of the licence is blunt: "No DBP Content may be downloaded or made available for offline use by any person or outside of DBP except for DBP Content that is accessible via the /download endpoint". Core Concepts adds the mechanism - call /download/list with your key for the filesets marked downloadable, then fetch each through /download/{fileset_id}/{book_id}/{chapter}. A /download/package-create path also exists.

The fences are real. Downloaded content "must remain within the application" and may only be consumed by the app tied to that key, your app must not let End Users reproduce or copy content, and this Limited Content Use "may be further limited or revoked by FCBH at any time upon written notice". Films are excluded outright. Media URLs are signed CloudFront links with a one-day expiry in the server code, so a cached URL is not a cached file.

Video: LUMO Gospel Films with a rights sheet attached

Video is a genuine part of the catalogue rather than a marketing line. The Gospel Films are LUMO productions that use the Gospel texts as their scripts word for word, with Faith Comes By Hearing audio dubbed on, which is why the count tracks the audio programme rather than a video one. The 2022 inventory shows 1,058 language codes with at least one film. Delivery is mp4 over multi-bitrate HLS, and there is a dedicated /arclight/jesus-film/languages route.

The licence attaches restrictions to the films that it attaches to nothing else, because the films are sublicensed to Faith Comes By Hearing rather than owned. They are "not for commercial use", must be free of advertising in any social format, may be posted online only in segments of 10 minutes or less inside the USA, its territories and Canada, and full-length showings there are limited to church, educational institution or prison premises. End Users may never download them, live-streaming is barred, broadcast requires a separate agreement, and the films may not be used to appeal for money.

Pricing

Best value

Free API key

Free

The only public tier. Request a key at 4.dbt.io/api_key/request with your name, email, application name, application URL and a description of intended use, then accept the API License Agreement. Section 6 of that agreement states no licence fees or other payments are due. What funds it is donations: Faith Comes By Hearing is a 501(c)(3) non-profit, federal tax ID 85-0223225, and every page of the developer site carries a "give" appeal rather than a pricing link.

Restricted key for additional content

Not published

The developer documentation invites you to make contact if you want content that is not currently exposed, "either fully available to all, or via a restricted API key". No price, no eligibility criteria and no turnaround time are published for this, and the practical route is the contact form.

Approved Sharing Addendum

Not published

Section 4 of the licence describes a separately executed addendum under which some licensees get access to subsets of content beyond the standard grant, and broader offline rights, "on terms acceptable to us". Nothing about who qualifies or what it costs is published, and any expanded right can be limited or revoked on written notice.

There is one price and it is zero. The API License Agreement addresses fees in a single sentence at Section 6: "No license fees or other payments will be due under this Agreement in exchange for the license granted by us to you for the API in Section 2." No metering, no seat count, no per-translation charge, no paid support tier.

The cost is passed to you as a constraint instead. The same agreement makes free access to your End Users a condition of the licence, so the money you cannot make is the payment. A donation-funded app, a church-funded app or a grant-funded app is fine. A $2.99 app that includes this content is not, and neither is a subscription tier that gates it.

The licence tightens the same screw from the other side, quoting the end-user terms back at developers as the baseline: content licensors permit users to "access the DBP Content solely through DBP (and not separately through offline download) for your personal, non-commercial use on a single device owned or otherwise controlled by you", and "Other uses are not permitted without further consent". Anything wider needs the unpriced Approved Sharing Addendum.

Note the liability arithmetic before building a business-critical dependency. The API is "AS IS" and "AS AVAILABLE" with all warranties disclaimed, aggregate damages are capped at $1,000.00, claims must be brought within one year, and disputes go to "binding and confidential Christian arbitration before a panel of arbitrators reasonably acceptable to FCBH" under New Mexico law. For a free API that is not unusual; it is worth reading before it matters.

Where Bible Brain API falls behind

No commercial use, stated as a condition rather than a suggestion. This is the single fact that decides whether Bible Brain is available to you. API.Bible draws the line differently, distinguishing usage tiers and letting some publishers license text into paid products; Bible Brain simply requires that End Users pay nothing for the content. If your roadmap includes any paid surface that surfaces this audio, stop here.

Documentation that has drifted, in ways a developer hits on day one. The licence and the end-user terms both read "Last Modified: 4/15/21", and the licence defines the API Site, the available-content list, the DBP Terms and Conditions and the third-party terms by URL on www.digitalbibleplatform.com - addresses that no longer serve those pages. The terms link now resolves to a 404 under faithcomesbyhearing.com, even though the licence obliges you to hand a copy of those terms to every End User. The live copy sits at /bible-brain/terms-conditions, which the licence does not mention.

An OpenAPI definition that contradicts the rest of the site. The file at 4.dbt.io/open-api-4.json declares version "4.0.0-beta", a termsOfService of "http://digitalbibleplatform/terms/" that is not a valid host, an externalDocs link to www.biblebrain.com that does not resolve, and a single server entry of "http://localhost:8080/api" labelled "Production Server". It also declares a licence of "Apache 2.0" while the repository README says MIT and the content is governed by neither. Point a code generator at it and you get a client that calls localhost.

No published rate limit, no published SLA, no official SDK. The developer site says nothing about quotas. The open-source server config carries throttle:1500,5, which in Laravel means 1,500 requests per five minutes, or roughly five per second - useful, but it is a number from a code repository rather than a commitment. There is no first-party client library in any language; the primary documentation artefact is a Postman collection.

Content that can disappear underneath you. Access control resolves an access type from the geolocated IP of the caller before deciding which filesets exist for a key, so coverage varies with where the request originates, and the licence warns that some translation licensors bar redistribution through development partners, so Faith Comes By Hearing may "freely remove, restrict, or limit access to all or any part of DBP Content at any time without liability to you".

Bible Brain vs. API.Bible vs. Free Use Bible API

These three cover the same nominal job and almost no overlapping ground. Free Use Bible API is the frictionless option: static JSON on a CDN, no key, no signup, 1,256 translations in 1,004 languages, and nothing but text. API.Bible is the publisher-relations option, with a large licensed text catalogue, a documented developer portal and defined usage tiers. Bible Brain is the only one of the three whose centre of gravity is recorded speech.

Put the audio question first and the field collapses. If your users listen rather than read, Free Use Bible API has nothing for you and API.Bible has text plus a modest audio selection from a few publishers. Bible Brain has dramatized multi-voice recordings with background music across a catalogue whose own 2022 inventory counted 1,381 language codes with audio, verse start times for 231 Bibles, 16kbps Opus for bad networks, and permission to cache marked filesets offline. That combination does not exist anywhere else at any price.

The trade is legal, not technical. Free Use Bible API asks nothing and guarantees nothing, and its copyright position is looser than it advertises. API.Bible makes you register and respect per-version publisher terms, but a commercial product is a conversation you can have. Bible Brain gives you the richest catalogue of the three and forecloses that conversation entirely, while adding an approval gate, a doctrinal condition and a right of revocation at any time. Choose on which of those you can accept, not on the endpoints.

The bottom line

Bible Brain is the most interesting free Bible API in existence and the most constrained. Nobody else hands a developer dramatized audio Scripture in over a thousand languages, verse-level timings, 16kbps Opus for bad connections and written permission to cache marked filesets offline, for nothing. The price is that your app can never charge for it, your key can be revoked at will, and you will read the server source to answer questions the docs should have answered. For free Scripture access aimed at people who cannot read the text, that is a bargain. For a business, it is a dead end - and the licence says so in Section 2.

Alternatives to Bible Brain API

API.Bible 4.0The other major keyed Bible API, run by the American Bible Society with a documented portal and defined usage tiers. Much stronger on licensed text and publisher relations, far thinner on audio, and the route to take if your product needs to earn money.

Free Use Bible API 4.0Static JSON on a CDN with no key and no signup, covering 1,256 translations in 1,004 languages. The fastest way to get Scripture text into a prototype, and no help at all if you need audio.

Bible.is 4.7Faith Comes By Hearing's own free app and website, built on this same catalogue. Worth installing before you write any code, because it shows you what the API can actually deliver in a given language.

JESUS Film Project 4.5A free video-first alternative for the same oral-audience problem, streaming the JESUS film and companion shorts in more than 2,000 languages. Narrower in scope, since it is film rather than a Scripture catalogue.

Bolls Bible 3.5A keyless public API covering 146 translations in 31 languages, with bulk JSON and ZIP downloads the developer actively encourages. Tiny by comparison and text-only, but the least friction of anything here.

Frequently asked questions

Is Bible Brain really free, and can I build a paid app on it?

Free, yes: Section 6 states that no licence fees or other payments are due. Paid app, no. The licence permits use only if "You enable your End Users to access DBP Content completely free of charge", so subscriptions, paid downloads and gated premium tiers that include this content are out. Donation-funded, church-funded and grant-funded apps are fine.

How many languages does it actually cover for audio versus text?

The figures on offer disagree, and it matters which is which. The Bible Brain page states text in 1,477 languages and gives no audio count. The content inventory CSV linked from the Available Content page, last modified 4 May 2022, lists 1,666 language codes overall: 1,381 with audio, 1,263 with text, 1,058 with video. Directory listings say 2,695, and the Faith Comes By Hearing homepage advertises "Audio Bibles in 2,749 languages and counting" for the whole recording programme, which is not the set an API key reaches.

How do I get an API key and how long does approval take?

Submit the form at 4.dbt.io/api_key/request with your name, email, application name, application URL and a description of how you will use the key, and accept the licence. The licence says Faith Comes By Hearing "may approve or deny your API Key request at our sole discretion" and that keys may be revoked or limited at any time. No turnaround time is published. Keys used within the last year on the older DBP version 2 still work on version 4.

What is the rate limit?

None is documented on the developer site. The open-source server configuration applies throttle:1500,5 to the API middleware group, which in Laravel means 1,500 requests per five minutes. Treat that as observed behaviour rather than a promise, and note that requests rejected for a missing or invalid key return no rate-limit headers, so you cannot discover your remaining quota from a failed call.

Can I cache or download the audio for offline use?

Only the filesets Faith Comes By Hearing marks as downloadable. Call /download/list with your key to see which qualify, then fetch chapters through /download/{fileset_id}/{book_id}/{chapter}. Everything else is streaming only; the licence states no content may be downloaded or made available offline except through that endpoint. Downloaded content must stay inside your app and may only be consumed by the app tied to that key, and Gospel Films may never be downloaded. Media URLs are signed CloudFront links with a one-day expiry in the server code, so a stored URL is not a stored file.

Does it provide verse-level audio timing data?

Yes, for part of the catalogue. The /timestamps endpoint lists the filesets that have timing metadata and /timestamps/{fileset_id}/{book}/{chapter} returns the per-verse start times. The documentation quotes 231 distinct bibleIds as of January 2022 and calls the values approximate. Since no figure has been published since, query the endpoint and count what your key can see. The documented uses are karaoke-style text highlighting against playing audio, and jumping playback to a search hit.

What are the doctrinal conditions on using the API?

Section 2 requires that you use the API, platform and content in accordance with the Faith Comes By Hearing Statement of Faith and Mission Statement, and only allow access "in a way that brings glory to God". Section 3 makes you responsible for End User conduct, including restricting users you see breaching those guidelines. Whatever tradition you serve, this is a licence condition rather than a preference, and a project that cannot accept it should use a different API.

Bible Brain API