Kaizen #203 - Answering Your Questions | Handling API Limits and Error Responses

Kaizen #203 - Answering Your Questions | Handling API Limits and Error Responses



Hi Everyone,
Welcome back to yet another post in the Kaizen Series! 
We appreciate your keen participation in the 200th milestone celebration of the Kaizen series. We will continue to answer the queries we received through the feedback. 
When working with Zoho CRM APIs, you must respect API limits, handle errors properly, and deliver meaningful experiences—even when things go wrong. In this post, we will discuss handling API limits and error responses.

Understanding Zoho CRM API Limits

Zoho CRM enforces API limits based on the purchased user licenses and add-on credits, and this is to ensure availability to all users and prevent abuse of its APIs. The following limits are applicable to Zoho CRM REST APIs.

  • API Credits Limits: Each edition (Free, Standard, Professional, etc.) comes with a set number of API credits per rolling 24-hour window. For example, Enterprise/Zoho One offers a baseline of 50,000 plus 1,000 per user license, with a cap up to 5,000,000 credits including add-one credits. You can refer to our help documentation on API limits for more details.
  • Concurrency Limits: Concurrency is the number of parallel API calls that are active at one time instance. Apps are capped at concurrent requests based on CRM edition: Free (5), Standard (10), Professional (15), Enterprise (20), Ultimate (25).
  • Sub-Concurrency Limits: Some resource-intensive APIs have their own concurrency limits (typically 10 concurrent requests): bulk updates, queries, lead conversion, mail, etc. Exceeding these returns a TOO_MANY_REQUESTS error.
  • Limits per Call: Different APIs have specific limits for the number of resources that can be inserted/updated. For example for insert, update, or upsert records, you can pass up to 100 records in one API call. Refer to the individual help documentation for any such limits.

Tips:

  • Monitor Usage: Use Zoho’s dashboard to track API credits in real time. Set alerts if you are approaching limits. Alternatively, keep an eye on the header X-API-CREDITS-REMAINING which denotes the remaining credits that will be present in the response when your API usage exceeds 50 percent or the daily available credit limit. Also, you can customize your usage notification to receive an email alert.
  • Batch Operations: Prefer bulk inserts/updates (up to 100 records/call) to reduce wasteful requests. Use composite APIs when multiple APIs need to be executed. 
  • Space Out Calls: When integrating, use logical intervals and avoid call bursts to prevent concurrency /subconcurrency limit getting applied. We have covered this in more detail in our previous Kaizen post : How to effectively handle API calls to optimize API credits?

Limits in Zoho CRM GraphQL APIs

Like our REST APIs, our GraphQL API calls also consume credits based on the type and number of resources queried. Maximum allowed credits per call is 10 credits.
Complexity for each query is calculated based on the type and number of resources requested, and maximum allowed complexity is 1,000 per query. 
Depth refers to the number of nesting layers of a field. Depth up to seven for metadata and three for records is allowed.
You can refer to our GraphQL API documentation on Credits, Complexity, and Depth for more details.

Handling Errors

 Zoho CRM REST APIs return 200 status codes for every successful API call. Each API error has these sections:
  • Status Code 
  • Error Code 
  • Message 
Different sections of an error response
Here "resource_path_index": 0 in the response indicates which segment of the URL path contains the error, counting after the API version.

Common Errors

  • 400 Bad Request:  
    • INVALID_MODULE
      • Cause: Incorrect module name (e.g., "Lead" vs "Leads").
      • Fix: Use exact API names from Setup > Developer Space > APIs.
    • INVALID_DATA
      • Cause: Malformed JSON/wrong data type.
      • Fix: Validate field formats.
    • DUPLICATE_DATA
      • Cause: Unique field value exists elsewhere.
      • Fix: Disable "Do not allow duplicates" or change value.
    • MANDATORY_NOT_FOUND
      • Cause: Missing required field (e.g., Last_Name in Contacts while trying to insert a new record in Contacts module).
      • Fix: Include all mandatory fields in the request.
  •  401 Unauthorized: 
    • AUTHENTICATION_FAILED
      • Cause: Wrong domain URL .
      • Fix: Use the correct domain-specific URL.
    • INVALID_TOKEN:
      • Cause: Expired OAuth token is used for making API call.
      • Fix: Refresh access token using the refresh token.
  • 403 Forbidden: 
    • NO_PERMISSION
      • Cause: User lacks permission for the resource.
      • Fix: Obtain necessary permission to access the resource.
  •  404 Not Found: 
    • INVALID_URL_PATTERN
      • Cause: URL syntax error.
      • Fix: Verify endpoint structure in API docs.
  •  429 Too Many Requests: 
    • TOO_MANY_REQUESTS
      • Cause: Number of API requests for the 24 hour period is exceeded or the concurrency/sub-concurrency limit of the user for the app is exceeded.
      • Fix: Make calls in accordance with the limits.
  • 207 Multi-Status: 
    • In some cases when the API is partially successful, 207 status code is returned.

Tips

  • Mandatory Fields: Provide all mandatory fields in the response body.
  • OAuth Issues: Ensure correct scopes.
  • Inspect Every Response Body: Parse responses even if the HTTP status code returned is 2XX. 
  • Validate Data Before Calling: Ensure your request matches the expected format. Clean data before submission to prevent 400-range errors (e.g., MANDATORY_NOT_FOUND, DUPLICATE_DATA).
  • Token Issues: Respond to INVALID_TOKEN with a token refresh workflow.

Error Status Code in GraphQL APIs 

Zoho CRM GraphQL APIs return errors in 200 and 400 status codes depending on error type. 200 HTTP status codes are returned in two cases. 
(a) Issue in the input when validated against the schema .
(b) Runtime errors due to credits, depth, and so on.

Refer to the Status Codes and Responses page in GraphQL for more information.
We hope you found this post useful. We will be back next week to answer another query we received.
Let us know if you have any questions in the comments or drop us an email at support@zohocrm.com.

    • Sticky Posts

    • Kaizen #217 - Actions APIs : Tasks

      Welcome to another week of Kaizen! In last week's post we discussed Email Notifications APIs which act as the link between your Workflow automations and you. We have discussed how Zylker Cloud Services uses Email Notifications API in their custom dashboard.
    • Kaizen #216 - Actions APIs : Email Notifications

      Welcome to another week of Kaizen! For the last three weeks, we have been discussing Zylker's workflows. We successfully updated a dormant workflow, built a new one from the ground up and more. But our work is not finished—these automated processes are
    • Kaizen #152 - Client Script Support for the new Canvas Record Forms

      Hello everyone! Have you ever wanted to trigger actions on click of a canvas button, icon, or text mandatory forms in Create/Edit and Clone Pages? Have you ever wanted to control how elements behave on the new Canvas Record Forms? This can be achieved
    • Kaizen #142: How to Navigate to Another Page in Zoho CRM using Client Script

      Hello everyone! Welcome back to another exciting Kaizen post. In this post, let us see how you can you navigate to different Pages using Client Script. In this Kaizen post, Need to Navigate to different Pages Client Script ZDKs related to navigation A.
    • Kaizen #210 - Answering your Questions | Event Management System using ZDK CLI

      Hello Everyone, Welcome back to yet another post in the Kaizen Series! As you already may know, for the Kaizen #200 milestone, we asked for your feedback and many of you suggested topics for us to discuss. We have been writing on these topics over the
      • Recent Topics

      • Can multiple agents be assigned to one ticket on purpose?

        Is it possible to assign one ticket to two or more agents at a time? I would like the option to have multiple people working on one ticket so that the same ticket is viewable for those agents on their list of pending tickets. Is something like this currently
      • Related Lists filter

        I have Contacts showing in our Accounts module. I customized the Contacts module with an Employment Status field, with the following picklist options: "Primary Contact", "Secondary Contact", "Active Staff(not a main contact)", and "No longer employed".
      • Standalone custom function not generating logs

        Why dont't standalone custom functions generate logs when the're called from another function? I have some functions (workflow, buttons and blueprint) that have common parts, so I put that part in a standalone function which is called from the others.
      • Automated log-out/session end

        I'm concerned about security of our data. Is it possible to set an automatic time-out for user sessions on Zoho CRM, after a certain period of inactivity or when the session reaches a certain duration (12 hours perhaps)? 
      • Add "Reset MFA" Option for Zoho Creator Client Portal Users

        Hello Zoho Creator Team, We hope you are doing well. We would like to request an important enhancement related to Multi-Factor Authentication (MFA) for client portal users in Zoho Creator. Currently, Creator allows us to enforce MFA for portal users,
      • Support Bots and Automations in External Channels

        Hello Zoho Cliq Team, How are you? We actively use Zoho Cliq for collaboration, including with our external developers. For this purpose, external channels are a key tool since they work seamlessly within the same interface as all of our other channels
      • Urgent Security Feature Request – Add MFA to Zoho Projects Client Portal Hello Zoho Projects Team,

        Hello Zoho Projects Team, We hope you are doing well. We would like to submit an urgent security enhancement request regarding the Zoho Projects Client Portal. At this time, as far as we are aware, there is no Multi-Factor Authentication (MFA) available
      • Creator HTML page refresh

        Hi, I have added around 5 different html snippets in single creator page. I understand, I can refresh the entire page from page script using Navigational URLs https://help.zoho.com/portal/en/kb/creator/developer-guide/others/url-patterns/articles/navigational-urls
      • Zoho Desk - Custom Module Related List Columns on Tickets

        I have a custom module in Zoho Desk called Asana Tasks, each task has a lookup to a Ticket. On the Ticket I want to see the columns of the Asana Tasks in the related list . Is there a way to do this? Right now it just has the name of the record and I
      • Google Analytics import data inaccurate (as of October 11, 2025)

        We have Zoho Analytics connected to GA4 to import daily event data. This has been running without issue for a couple of years. However, a month ago we started noticing discrepancies. All data until October 10 lines up perfectly - October 11 onward is
      • What is your opinion of the new UI?

        Hi Everyone, I would like to see what everyone thinks of the new Zoho One Dashboard. I don't get it, but perhaps I'm missing something. What are your thoughts?
      • Zoho mail to Teaminbox

        Hello, We're searching for new mail program. Now I'm testing a bit with zoho mail and team inbox. My findings in the research: Pop mail throught zoho mail is almost instant. Any pop or imap via external provider takes a couple minutes to 15 minutes before
      • What are the OAuth scopes needed to access the Zoho MCP server?

        I think I'm authenticating with the MCP server endpoint successfully using a bearer token but I can't successfully initialize an MCP session. I'm using the official MCP Python sdk (https://github.com/modelcontextprotocol/python-sdk). I get as far as here
      • Account blocked for IMAP use

        Hello, My email client (Evolution) can't sync mail anymore. It gives the error: "Your account is temporarily blocked for IMAP use. This may happen if you exceed the maximum number of simultaneous IMAP connections allowed. Kindly try again after some time."
      • Is SMTP included in the free plan?

        My client has a Zoho Mail Free 14 day trial that ends tomorrow. She has set up a domain email address with SMTP on a third party app and is wondering if it will continue working once her plan downgrades to the free forever plan. Thanks
      • Zoho mail issue.

        I have verified my domain ohhoexpress.online by adding necessary TXT and MX records. But when I am sending email to any external email id, it is showing as zohomail.com. Also while I am sending mail to internal mail id, it is saying user not found whereas
      • My email is blocked from sending

        I get this message when I try to send any message .. > Unable to send message, Reason 554 5.1.8 Email Outgoing Blocked We have urgent emails to send and the issue continues to persist from yesterday. Please help us with this issue as soon as possibl
      • [WEBINAR] Smooth year-end closure with Zoho Books (KENYA)

        Hello there, This webinar is for all Kenyan businesses looking to wrap up their financial year smoothly! Join our free session to learn how Zoho Books can simplify your year-end process. What to expect from this webinar: - All the latest updates in Zoho
      • cannot recieve or send emails

        we are not recieving or cannot send emails.Shows sysytem error
      • Zoho Sites - contact us form

        I have added a contact us form to my website. I wanted to change the layout so I deleted the section of Contact Us form. When I again try to add the section of Contact Us form, it shows error that "This form already exists on this page."  I am unable
      • switching from POP3 to IMAPI do I need to change settings in Web email?

        hi so I am using Outlook with My Zoho mail, also have Verizon email /AOL. they no longer support POP3 and said imapi is much better, so I want to switch my ZoHo to imapai. I googled and it said i need to change it in my account....i looked at my account
      • What functionality is new in the Z025 Spaces UI dashboard compared to the previous Zoho One dashboard?

        My company is interested in creating a revamped dashboard this coming year, and are trying to weigh different platform options. The new Spaces UI is said to be a more "feature-rich" dashboard experience than the previous. Could a developer please explain
      • Collections Management: #5 Convenience on Offer, using Self-Checkout

        "Is this the right page? Oh, now, it wants my address again. Why am I being redirected?" These were the exact thoughts running through Karan's mind as he tried to subscribe to an application he genuinely liked. He clicked "Buy Now", expecting a quick
      • Uploading a signed template from Sign to Creator

        Good day, Please help me on how to load a signed document back into Creator after the process has been completed in Sign. Below is the code that I am trying, pdfFile = response.toFile("SignedDocument_4901354000000372029.pdf"); info pdfFile; // Attach
      • PROBLEMA

        Salve, non riesco a inviare email, e mi esce una tabela errore temporaneo. come posso risolvere il problema ?
      • Tip #50- A Closer Look at the Unattended Access Dashboard- 'Insider Insights'

        Having complete visibility and quick access to everything you need certainly makes managing multiple remote devices a lot easier, and that is precisely what the Unattended Access Dashboard in Zoho Assist is designed to offer. Once you go to the Unattended
      • How to update custom multi-user field in Zoho Projects?

        I'm trying to update custom multi-user fields in Zoho Projects via a Deluge function in CRM. The code I have so far is below. It works for updating standard project fields and single-line custom fields, but it does not work to update multi-user fields.
      • Tip of the Week #75– Manage your social media messages from a single shared inbox.

        Are you tired of jumping between apps or browser tabs to reply to your business's Facebook and Instagram DMs? Handling customer messages on social media might seem simple, but switching between multiple platforms can easily lead to lost messages, duplicate
      • Zoho Map integration tasks have changed - you need to "Locate all instances of Zoho Map integration tasks in your Deluge scripts by searching for the v1 marker... before 16 January 2026"

        The Zoho Map deluge integration task has been changed (as at 21 October 2025) to provide a more structured, JSON-like response. This change affects all three Zoho Map integration tasks (Geocode, Reverse Geocode, and Distance Between). More details can
      • Using files from Zoho CRM in Gemini/ChatGPT/Claude

        Hi all, I’ve got subscriptions to Gemini and a few other AI tools which I use for tasks like data enrichment, email composition, etc. In our workflow, we often receive various documents from clients — such as process workflows, BRDs/requirement documents
      • Zoho Analytics & Zoho Creator - Modified Time value

        I'm trying to use the Zoho Creator system field 'modified time' in Zoho Analytics, but it's consistently showing 12 hours 'out' In Zoho Creator In Zoho Analytics Is this a constant difference that I just need to correct with a timezone change - or is
      • Zoho CRM - Option to create Follow-Up Task

        When completing a Zoho CRM Task, it would be very helpful if there was an option to "Complete and Create Follow-Up Task" in the pop-up which appears. It could clone the task you are closing and then show it on the screen in edit mode, all the user would
      • Portal For Different Apps

        I found some older threads on this but didn't see anything very recent. I'm new to Zoho One so forgive me if my terminology is off a bit. I was hoping set up a single point of entry into Zoho One. So, many of the apps could be found in one single place
      • Calls undetected

        Zoho Voice records indicate my last call ended at 6:00 PM. All incoming and outgoing calls occurred between 6:00 PM and 7:00 PM.
      • Unable to Select Authenticated Domain as Sender

        We’ve already authenticated our domain, but it’s still not appearing in the sender list when we try to run a campaign. Could you please check what might be causing this issue?
      • Forever FREE Business Email with Zoho Mail

        Forever FREE Business Email with Zoho Mail: is it available?
      • Zoho Projects - Project Details on the Project Menu

        Hi Project's team, I've helped may businesses setup and use Zoho Project and one thing I see time and time again is confusion on where to find the Project Details information. I would be much more intuitive if Project Details was on the menu before Dashboard.
      • Introducing WhatsApp integration in Bigin

        Greetings! In today's business landscape, messaging apps play a significant role in customer operations. Customers can engage with businesses, seek support, ask questions, receive personalized recommendations, read reviews, and even make purchases—all
      • Zia Conversation Summary: Context at a glance for every customer interaction

        Hello everyone! Every customer conversation tells a story—but in CRM, that story is rarely in one place. A sales rep moving between multiple leads has to reopen long email threads, check call remarks, and revisit meeting notes just to remember what was
      • Zoho Projects - Show Task List as dropdown field on Task records

        Hi Project's Team, I noticed today that there is no field on a task record related to the task list it belongs to. A dropdown would be helpful for quickly moving tasks between lists while in a task. I know that you can go to "Other Actions" and choose
      • Next Page